J.  H . Under'S  Ore 


N[ode,m  /Vlei-hods  Of  Highway 


MODERN  METHODS 

OF 

HIGHWAY  CONSTRUCTION 

BY 

JOHN  HENNING  ANDERSON 
B.  S.,  University  of  Illinois,  1914 


THESIS 

Submitted  in  Partial  Fulfillment  of  the  Requirements  for  the 

Degree  of 

CIVIL  ENGINEER 

IN 

THE  GRADUATE  SCHOOL 

OF  THE 

UNIVERSITY  OF  ILLINOIS 


1921 


\ 


¥ 


■* 


UNIVERSITY  OF  ILLINOIS 


\V~L\ 

THE  GRADUATE  SCHOOL 

March  26, 19?  1 

I HEREBY  RECOMMEND  THAT  THE  THESIS  PREPARED  BY 

JOHN HMNING ANDERSON 


ENTITLED  

_ MODERN  METHODS  OF  HIGHWAY  .CONSTRUCTION.  

BE  ACCEPTED  AS  FULFILLING  THIS  PART  ON  THE  REQUIREMENTS  FOR  THE 

PROFESSIONAL  DEGREE  OF  -....CIVIL  ENGINEER. - 

Head  of  Department  of  Civil Engine  sring  , 


Recommendation  concurred  in  : 


Committee 


4 


-,45 


j 


Digitized  by  the  Internet  Archive 

in  2016 


https://archive.org/details/modernmethodsofhOOande 


TAB  IE  OP  CONTENTS 


CHAPTER  PAGE 

I.  THE  PROBLEM  OP  HIGHWAY  CONSTRUCTION 1 

II.  METHODS  OF  HIGHWAY  CONSTRUCTION 3 

III.  RATE  OF  CONSTRUCTION 13 

IV.  THE  APPLICATION  OF  LIGHT  RAILWAY  TO  HIGHWAY  CONSTRUCTION  . 20 

V.  TYPES  OF  LIGHT  RAILWAY  PLANT 31 

VI.  GRADES,  SPEED  AND  SIZE  OF  TRAINS 37 

VII.  TRAIN  SCHEDULES  AND  LOCATION  OF  SIDINGS 48 

VIII.  PLAN  OF  OPERATION 51 

IX.  HAULAGE  EQUIPMENT  REQUIRED 58 

X.  MATERIAL  UNLOADING  AND  PROPORTIONING  YARD 71 

XI.  PERSONNEL  REQUIRED 90 

XII.  COST  OF  OPERATION  . 98 

XIII.  THE  ADVANTAGES  AND  ECONOMIES  OF  LIGHT  RAILWAY  HAULAGE  . . Ill 

XIV.  THE  MINIMUM  SIZE  OF  JOB  JUSTIFYING  A LIGHT  RAILWAY  PLANT.  . 118 

XV.  PRESENT  TENDENCIES  IN  HIGHWAY  CONSTRUCTION 123 


APPENDIX 

COMPARISON  OF  FABRICATED  TRACK  WITH  WOODEN  TIE  TRACK 

ITEMS  ENTERING  INTO  COST  OF  HIGHWAY  CONSTRUCTION 

A GUIDE  TO  ESTIMATING  CONSTRUCTION  EQUIPMENT  EXPENSE 

DRAWINGS  OF  MATERIAL  TUNNEL 

DRAWINGS  OF  200  CUBIC  YARD  STORAGE  BIN 

DRAWINGS  OF  TYPICAL  STEEL  BATCH  BOXES 

DRAWING  AND  SPECIFICATION  SHEET  OF  TYPICAL  PUMP 

CLEARANCE  DIAGRAM  OF  TYPICAL  14-E  PAVER 

DRAWING  AND  SPECIFICATIONS  OF  TYPICAL  BATCH  BOX  CAR 

ILLUSTRATIONS  OF  DIRECT  CHARGING  OF  PAVER,  CITY  STREET  CONSTRUCTION 

SPECIFICATION  SHEET  OF  TYPICAL  6 TON  LOCOMOTIVE 

INSTRUCTIONS  FOR  USING  SUBGRADER 

BULLETIN  ON  STEEL  FORMS,  THE  LAKEWOOD  ENGINEERING  COMPANY 
BULLETIN  ON  ROAD  PLANT,  THE  LAKEWOOD  ENGINEERING  COMPANY 


LIST  OF  ILLUSTRATIONS 


PAGE 

CHARGING  MIXER  BY  HAND 3 

WASTE  OF  MATERIAL  DUE  TO  DUMPING  ON  SUBGRADE  ....  4 

WASTE  MATERIAL  ON  SHOULDER  OF  ROAD 4 

CHARGING  MIXER  WITH  BELT  CONVEYOR 5 

PORTABLE  BUCKET  LOADER  HANDLING  MATERIAL  FROM  SUBGRADE  . 5 

DIRECT  CHARGING  OF  MIXER  BY  MEANS  OF  LIGHT  RAILWAY  . . 6 

MACHINE  TRIMMING  OF  THE  SUB  GRADE 7 

CHARGING  MIXER  DIRECT  FROM  TRUCK  .......  8 

MOTOR  TRUCKS  HAULING  MIXED  CONCRETE 8 

LIGHT  RAILWAY  HAULING  MIXED  CONCRETE 9 

LAKEWOOD  ROAD  FINISHING  MACHINE 10 

LAKEWOOD  SUB  GRADER 11 

EFFECT  OF  HEAVY  ROLLING  STOCK  ON  LIGHT  TRACK  ....  20 

V-BODY  CARS  CHARGING  SIDE  LOADING  PAVING  MIXER  ...  21 

DERAILMENT  RESULTING  FROM  POOR  HIACK  AND  EQUIPMENT  . . 21 

OLD  STYLE  TRACK  OF  INADEQUATE  CAPACITY 22 

WOODEN  TIE  TRACK 23 

SOIL  FLOW  CAUSED  BY  OPEN  END  TIES 23 

PLANKS  UNDER  TRACK  NECESSITATED  BY  INADEQUATE  TIES  . . 24 

PRESSED  STEEL  TIE  TYPE  OF  TRACK 25 

LAYING  LIGHT  RAILWAY  ffiACK  26 

WHITCOMB  6 TON  GASOLENE  LOCOMOTIVE 26 

LIMA  10  TON,  DOUBLE  TRUCK  STEAM  LOCOMOTIVE  ....  27 

PLYMOUTH  6 TON  GASOLENE  LOCOMOTIVE 27 

BATCH  BOX  SYSTEM  OF  LIGHT  RAILWAY  HAULAGE  ....  28 

DOUBLE  TRUCK  GENERAL  UTILITY  PLATFORM  CAR  ....  29 

BATCH  BOXES  CARRIED  ON  MOTOR  TRUCKS 32 

HAULING  MATERIAL  OVER  CURED  CONCRETE,  COMBINED  SYSTEM  . 33 

TRANSFERRING  BATCH  BOXES  FROM  TRUCK  TO  CARS  ....  33 

LIGHT  RAILWAY  CROSSING  HINGED  HORIZONTALLY  ....  35 

LIGHT  RAILWAY  CROSSING  HINGED  VERTICALLY 35 

COUNTERBALANCED  LIGHT  RAILWAY  CROSSING  HINGED  VERTICALLY  . 36 

TWENTY-FIVE  CAR  TRAIN  IN  ARIZONA 43 

THREE  CAR  TRAIN  ON  8.2  PER  CENT  GRADE  IN  PENNSYLVANIA  . 43 

BOOSTER  LOCOMOTIVE  METHOD  OF  NEGOTIATING  STEEP  GRADE  ♦ . 44 

MOTOR  TRUCKS  HAULING  TRAIN  UP  STEEP  GRADE  ....  45 

LOCOMOTIVE  ATTACHED  TO  TRAIN  AT  MIXER 59 

SWITCHING  OARS  WITH  A HORSE 60 

SWITCHING  CARS  BY  HAND 60 

PASSING  SIDING  NEAR  MIXER 61 

GENERAL  UTILITY  PLATFORM  CAR 64 

BATCH  BOX  HAULAGE  ’WITH  3- i/2  TON  TRUCK 65 

LOADING  TRUCK,  BATCH  BOX  HAULAGE  SYSTEM 66 


* 


LIST  OF  ILLUSTRATIONS 


PAGE 

TRANSFERRING  BATCH  BOXES  FROM  TRUCK  TO  CARS  ....  66 

PORTABLE  DERRICK  FOR  TRANSFERRING  BATCH  BOXES  ...  66 

LOCOMOTIVE  AT  TRANSFER  POINT 68 

TRAIN  APPROACHING  MIXER,  COMBINED  SYSTEM  ....  68 

PORTABLE  BIN  AT  TRANSFER  POINT 69 

TRUCK  CHASSIS  EQUIPPED  WITH  BATCH  BOX  FRAME  ....  69 

PORTAL  VIEW  OF  MATERIAL  TUNNEL 73 

SIDS  VIEW  OF  MATERIAL  TUNNEL 73 

LONG  MATERIAL  STORAGE  PILE 75 

MOVABLE  BIN  REHANDLING  PLANT 76 

LIGHT  RAILWAY  TRACK  IN  CENTER  OF  MOVABLE  BIN  TRACK  . . 77 

SMALL  STATIONARY  BIN  REHANDLING  PLANT 78 

SMALL  MATERIAL  DUMPING  TRESTLE 78 

TRESTLE  SYSTEM  OF  UNLOADING  MATERIAL 79 

STOCK  PILE  AND  BIN  METHOD  OF  HANDLING  MATERIAL  ...  80 

LARGE  MATERIAL  STORAGE  BIN 81 

TUNNELS  BENEATH  PILES  STORED  BY  DERRICK 81 

THE  SUNBURY  UNLOADER 82 

BIN  AND  BUCKET  ELEVATOR  SYSTEM 83 

METHOD  OF  HANDLING  BAGGED  CEMENT 83 

BULK  CEMENT  BIN  BETWEEN  SAND  AND  STONE  BINS  . . . .84 

HANDLING  BULK  CEMENT  BY  MOTOR  TRUCK 85 

VOLUMETRIC  METHOD  OF  MEASURING  BULK  CEMENT  ....  87 

BULK  CEMENT  WEIGHING  DEVICE 88 

MOVABLE  MATERIAL  HOPPERS,  ONE  LOAD  CAPACITY  ....  90 

DIRECT  CHARGING  OF  MIXER  WITH  5 TON  TRUCK  ....  93 

FORD  TRUCKS  WITH  SPECIAL  DUMP  BODY 93 

DERRICK  ON  WAGON  FOR  TRANSFERRING  BATCH  BOXES  ...  94 

MACHINE  TRIMMING  OF  THE  SUBGRADE 95 

BATCH  BOX  CHARGING  SYST3M Ill 

UNOBSTRUCTED  SUBGRADE  PERMITS  MACHINE  TRIMMING  . • .112 

RE  TRIMMING  SUBGRADE  DUE  TO  HtUCK  HAULAGE  . . . .113 

RUTTED  SUB  GRADE  DUE  TO  TRUCK  HAULAGE 113 

TRIMMING  SUBGRADE  BY  HAND 114 

MACHINE  TRIMMED  SUBGRADE 115 

LOST  MATERIAL  RESULTING  FROM  DUMPING  ON  GROUND  . . .116 

LIGHT  RAILWAY  HAULAGE  ELIMINATES  HEAVY  LABOR  . . .117 

BURTON  6 TON  LOCOMOTIVE  HAULING  8 CAR  TRAIN  . . . .120 


1 


MODEM  METHODS  OF  HIGHWAY  CONSTRUCTION 


CHAPTER  I. 


THE  PROBLEM  OF  HIGHWAY  CONSTRUCTION. 


The  highway  system  of  the  United  States  consists  of  some  2,250,000 
miles  of  public  road,  or  approximately  two-thirds  mile  of  road  per  square  mile 
of  area.  The  improvement  of  this  enormous  system,  sufficient  in  extent  to  girdle 
the  globe  100  times,  presents  a problem  which  in  many  ways  is  the  greatest  that 
has  ever  confronted  a people  for  solution.  Competent  authorities  have  estimated, 
however,  that  the  improvement  of  20  per  oent  of  the  total  mileage  will  provide  a 
trunk  line  or  primary  system,  which  will  carry  90  per  cent  of  the  traffic.  The 
improvement  of  this  primary  system,  consisting  of  some  450,000  miles  of  road,  or 
1 mile  of  road  for  every  7 square  miles  of  area,  is,  therefore,  our  first  object- 
ive* 

The  magnitude  of  the  highway  problem  can  perhaps  be  best  realized  by 
comparison  with  our  railroad  system,  to  the  development  of  -which  we  have  devoted 
same  70  years.  The  primaiy  highway  system  alone  exceeds  the  mileage  of  all  trunk 
and  branch  railroad  lines  by  some  40  per  cent*  The  cost  of  the  heavy  type  of 
construction  which  modern  traffic  makes  necessary  on  the  primary  system  will  at 
least  equal,  and  in  many  oases  exceed,  the  cost  of  the  railroads  at  the  time  of 
their  construction*  In  both  cost  and  mileage,  therefore,  our  highway  system  ex- 
ceeds the  railroad  system,  considering  merely  that  portion,  some  20  per  cent, 
herein  designated  as  the  primary  system* 

While  it  is  inpossible  to  estimate  the  length  of  time  that  will  be  re- 
quired to  complete  our  highway  system,  it  is  no  doubt  safe  to  say  that  a period  of 
time  considerably  shorter  than  70  years  will  be  allowed  by  an  impatient  public  for 
the  completion  of  at  least  the  450,000  miles  of  road  comprising  the  primary  system. 
The  value  and  necessity  of  good  roads  is  at  last  fully  realized,  and  ample  funds 
have  been  provided  by  the  publio.  The  demand  is  now  for  a comprehensive  system 
in  the  shortest  possible  time* 

It  has  been  estimated  that  approximately  $1,000,000,000  are  available 
for  highway  construction  in  1921,  while  about  two-thirds  of  this  amount  was  avail- 
able in  1920.  The  limiting  factor  to  quantity  product  ion  of  roads  to  date  has 
been  the  supply  of  raw  materials,  and  whether  or  not  the  material  supply  will  be 
adequate  to  permit  construction  at  a rate  commensurate  with  the  funds  available  is 
problematical.  Assuming,  however,  that  the  material  situation  will  be  properly 
adjusted  and  that  funds  available  will  be  maintained  at  the  rate  for  1921,  approx- 
imately 20  years  will  be  required  to  complete  the  primary  system  at  an  average 
cost  of  $40,000  per  mile.  To  complete  the  primaiy  system  in  20  years  will  entail 
construction  at  the  rate  of  24,000  miles  per  year.  This  rate  of  construction  of 
trunk  line  highway  is  considerably  greater  than  has  been  attained  to  date,  so  even 
allowing  for  a big  increase  in  the  rate  of  production,  due  to  improved  methods, 


2 


it  seems  that  an  allowance  of  20  years  for  completing  the  primary  system  is  about 
the  minimum  that  good  judgment  dictates  at  the  present  time.  Simultaneously 
with  the  construction  of  the  primary  system,  a considerable  amount  of  construction 
can  be  carried  on  in  the  cheaper  types  of  road  suitable  for  the  secondary  system. 

It  i6  not  the  province  of  this  thesis  to  deal  with  the  merits  of  any 
particular  kind  of  road  surfacing.  Suffice  it  to  say  that  the  consensus  of  opin- 
ion among  leading  highway  engineers  at  the  present  time  is  that  roads  with  a 
concrete  wearing  surface,  or  a concrete  base  to  support  some  other  type  of  wearing 
surface,  are  necessaiy  to  withstand  the  effects  of  the  heavy  traffic  which  our 
trunk  line  highways  will  be  subjected  to.  Inasmuch  as  the  construction  of  this 
type  of  road  is  the  most  difficult  and  costly,  this  thesis  will  deal  only  with 
methods  of  construction  of  so-called  permanent  roads.  The  methods  described  in 
this  thesis  will  apply  to  any  type  of  road  in  which  concrete  is  used  either  as  a 
wearing  surface  or  a base. 

Modern  heavy  traffic,  consisting  of  a vast  and  ever  increasing  number 
of  motor  trucks,  requires  much  heavier  construction  and  closer  attention  to  de- 
tails, than  was  considered  necessary  only  a few  years  ago.  Heavier  construction 
naturally  calls  for  the  use  of  a much  greater  quantity  of  material  than  formerly, 
and  the  work  of  handling  this  material  is  consequently  increased.  This  has  led 
to  the  extensive  use  of  machinery  to  replace  hand  methods,  not  only  on  account 
of  greater  economy  and  efficiency  but  also  due  to  the  necessity  of  increasing 
output. 

At  the  present  time  we  are  undertaking  the  biggest  road  building  program 
known  in  history,  in  spite  of  the  fact  that,  until  the  winter  of  1920-21,  the 
country  was  suffering  from  an  acute  labor  shortage  and  widespread  unrest . No 
doubt  this  labor  shortage  will  again  make  its  appearance  at  the  expiration  of  the 
present  temporary  period  of  depression.  In  order  to  overcome  labor  shortage, 
extensive  use  of  machinery  has  been  resorted  to  in  highway  construction.  It  is 
becoming  increasingly  difficult  to  secure  labor  to  perform  heavy  manual  work,  and 
this  again  has  led  to  the  extensive  substitution  of  machinery  for  hand  methods. 

It  has  been  the  experience  of  many  contractors,  that  labor  turnover  has  been 
greatly  reduced  by  the  elimination  of  heavy  manual  labor  thru  the  introduction  of 
machinery.  Mechanical  methods  also  lead  to  the  development  of  a higher  type  of 
labor  than  do  hand  methods. 

At  the  present  tiros  highway  construction  is  just  emerging  from  the 
"rule-of-thumb",  "hit-or-miss"  stage,  and  for  the  first  time  scientific  methods 
and  thoro  organization  are  being  given  proper  consideration.  Until  quite  re- 
cently road  building  has  been  considered  a small  man's  game,  and  even  now  some 
engineers  adhere  to  this  opinion.  The  demand  for  good  roads  is  so  great,  however, 
that  it  is  inpossible  to  supply  it  by  the  old  methods  of  operation.  Road  building 
is  no  longer  a small  man's  game,  and  it  is  now  attracting  some  of  the  largest 
contracting  organizations  in  the  country.  Contracts  for  $1,000,000  worth  of  work 
and  up  are  now  quite  common.  An  illustration  of  the  present  trend  in  highway 
construction  is  afforded  by  Maricopa  County,  Arizona,  where  a contract  for  288 
miles  of  concrete  road  was  awarded  to  one  contractor  in  1920. 

Due  to  the  fact  that  the  work  is  spread  out  over  such  a great  area  and 
the  concrete  mixers  are  frequently  many  miles  from  the  material  yard,  highway 
construction  is  essentially  a transportation  problem.  Greater  refinement  is 
necessary  in  highway  construction  than  in  most  any  other  class  of  work. 


\ 


3 


CHAPTER  II. 


METHODS  OF  HIGHWAY  CONSTRUCTION 

Until  2 years  ago  the  general  method  of  constructing  a road  in  which 
concrete  was  used  as  a wearing  surface  or  a base,  has  been  to  haul  the  aggregates 
from  the  material  yard  and  dump  them  on  the  subgrade  in  windrows.  The  aggregates 
were  then  loaded  into  wheelbarrows  by  means  of  shovels,  and  wheeled  to  the  charg- 
ing skip  of  the  mixer.  This  method  naturally  required  a large  number  of  wheelers 
and  shovelers,  the  average  size  wheelbarrow  load  approximating  3 cubic  feet.  To 
load  materials  for  a 4-bag  batoh  of  concrete  of  the  proportions  generally  used, 
required  a wheeling  and  shoveling  crew  of  at  least  16  men.  This  work  was  hard  to 
perform,  and  the  labor  turnover  in  the  charging  crew  was  generally  considerable. 
Occasionally  a few  hundred  feet  of  24 -inch  gavge  track  and  a few  dump  oars  were 
used,  loading  the  cars  by  hand  and  pushing  them  to  the  skip  of  the  mixer. 


CHARGING  LEXER  BY  HAND 


One  of  the  serious  objections  to  the  method  of  dumping  aggregates  on 
the  subgrade  is  the  cutting  up  of  the  subgrade  by  the  wheels  of  the  vehicles, 
particularly  for  a considerable  time  after  a rain.  Not  only  is  the  subgrade  badly 
cut  up,  but  serious  delay  is  frequently  incurred  due  to  the  inability  of  vehicles 
to  operate  over  the  subgrade  for  a number  of  days  after  a rain.  In  certain  clay 
soils  the  delay  caused  by  a rain  will  sometimes  amount  to  a week  or  more.  The 
seriousness  of  this  lost  time  during  the  construction  season  is  obvious. 

Another  serious  objection  to  the  dumping  of  aggregates  on  the  subgrade 
is  the  dirt  which  is  generally  mixed  with  the  material.  The  effect  of  this  for- 
eign matter  on  the  quality  of  the  pavement,  particularly  when  a concrete  wearing 
surface  is  employed,  is  apparent.  Not  only  is  dirt  mixed  with  the  aggregate  but 
a considerable  amount  of  aggregate  is  lost  to  the  ccnbractor  due  to  rejection  by 
the  inspector  because  of  the  dirt  mixed  with  it,  and  the  grinding  of  the  aggregate 
into  the  subgrade  by  the  wheels  of  the  vehicles  employed  in  hauling  it.  A number 
of  states  now  prohibit  the  dumping  of  aggregate  on  the  subgrade. 


. 


To  distrioute  aggregate  on  the 
suograde  in  proper  quantity  is  exceed- 
ingly difficult.  If  insufficient 
material  is  placed  it  is  very  diffi- 
cult to  replenish  the  supply  because 
of  the  oostruction  formed  by  the 
windrows  of  material  on  the  subgrade. 

A long  wheelbarrow  haul  generally 
results  until  additional  material  can 
be  brought  up.  If  too  much  material 
is  distributed,  it  is  generally  im- 
possible to  remove  the  surplus  with- 
out delaying  the  concrete  mixer.  The 
surplus,  therefore,  is  almost  always 
thrown  on  the  shoulder  where  it  is 
wasted. 


’VASTS  MATERIAL  OK  SUBGRADE. 


Dumping  the  aggregate  on  the  sub- 
grade precludes  the  use  of  a subgrade 
machine  for  trimming  the  subgrade, 
necessitating  expensive  and  inaccurate 
hand  trimming.  The  practice  of  dump- 
ing aggregate  on  the  suograde  also  en- 
tails (i  considerable  amount  of  retrim- 
ming,  due  to  the  ruts  formed  by  the 
vehicles. 


WASTE  MATERIAL  OK  SHOULDER. 

aw  


5 


Sometimes  a portable  belt  conveyor  is  used  in  charging  the  concrete 
mixer.  A typical  machine  of  this  class  is  that  manufactured  by  the  Koehring 
Machine  Company,  of  Milwaukee,  Wisconsin.  This  machine  is  equipped  with  a number 
of  hoppers  into  which  sand  and  stone  is  shoveled.  Each  hopper  is  of  predetermined 
capacity,  and  discharges  onto  the  belt  by  means  of  a door  in  the  bottom.  A con- 
veyor belt  of  this  type  will  eliminate  wheelers  but  will  require  the  same  number 
of  8hovelers,plus  an  additional  man  or  two  to  clear  the  way  for  moving  the  machine. 
A gasolene  engine  furnishes  the  power  for  the  operation  of  the  belt,  and  an  oper- 
ator must  be  detailed  to  take  care  of  the  engine.  This  method  of  construction 
does  not  eliminate  dirt  in  the  aggregates,  nor  waste  due  to  dumping  on  the  sub- 
grade. The  obstruction  formed  by  the  windrows  of  material  likewise  precludes 
mechanical  trimming  of  the  subgrade.  While  the  loading  belt  has  been  used  to  a 
considerable  extent  during  the  past  two  years,  the  consensus  of  opinion  among 
contractors  is  that  this  method  is  not  economical.  Naturally  this  method  of  con- 
struction cannot  be  used  where  specifications  prohibit  dumping  material  on  the 
subgrade,  or  permit  it  to  be  dumped  only  in  piles  1,000  feet  or  so  apart. 


PORTABLE  BUCKET  LOADER  HANDLING  MATERIAL  FROM  SUBGRADE 


CHARGING  MIXER  WITH  BELT  CONVEY® 


d eldstrocr  s s& 
axiict  lo  enixiosm  I 
>03  iW  ,ee?lJxsv;IiM  lo  f 
extol  a fins  Jbxiea  riolriw  o 
Jlecf  exii  olxxo  aegiario^ii) 

.«•  ei-sxxifnile  II iw  eq^J  slxil  \ 
jvrt  10  xtGn  iBiioI  3 ibbs  as  suLq,s 
.i  icl  isvvoq  oil 3 sodslsrxifi  saiga© 

$as  exi 3 ‘io  eiso  e>Js3  od  belisieb  ed 
•ic a .39^x3§9i^je  ©xtt  ni  Six!)  etsnlmile 
'O ihnivJ  &ti$  Y,d  b&miol  noi  I oi;i J arf o silT 
rixlW  .sJbBigcfoa  erU  Io  ^hIotuIiI  Iso. 
owj  J&sq  9rii  gniiaJb  iasixe  ©IcTsie* 

~in  si  Jbcxidsra  aixitf  io/ltf  si  aioJosx 
'9q3  eisrfw  Jbeax;  ecf  Ioxuxbo  noi^o. 
-Tx/Jb  9gT  oJ  ii  Sxrrrteq  io  f9£)£igv 


6 


Sometimes  a small  amount  of  light  railway  track:  is  used  to  haul  material 
from  piles  on  the  subgrade  one-half  mile  or  so  apart*  To  load  the  hatch  boxes  a 
portable  bucket  loader  is  frequently  employed,  as  shorn  in  the  foregoing  illustra- 
tion. A power  soraper  is  used  to  scrape  material  up  to  the  bucket  loader,  as 
shown.  Power  for  operating  this  scraper  is  obtained  from  the  engine  driving  the 
bucket  loader.  This  method  is  more  economical  than  the  method  of  dumping  material 
in  long  windrows,  as  there  is  less  chance  for  loss  of  material.  The  same  objec- 
tions due  to  cutting  up  the  subgrade,  delay  from  rain,  etc.  apply  to  this  method 
with  almost  equal  force  as  those  which  apply  to  the  windrow  method. 

When  teams,  motor  trucks,  or  tractors  are  used  for  hauling  material  it 
is  necessary  to  begin  laying  concrete  at  the  most  distant  point  from  the  material 
yard,  or  at  some  other  point  between  the  material  yard  and  the  far  end  of  the  road 
provided  side  roads  are  available.  This  is  due  to  the  impossibility  of  hauling 
past  the  uncured  ooncrete,  as  there  is  very  seldom  sufficient  room  on  the  shoulder 
of  the  road  for  the  operation  of  teams,  trucks,  or  tractors.  When  this  method  of 
haulage  is  employed,  therefore,  it  is  generally  necessary  to  delay  placing  concrete 
until  the  grading  between  the  material  yard  and  the  far  end  of  the  road  is  complete 
At  times  this  delay  might  be  reduced  by  hauling  material  thru  the  grading  opera- 
tions, but  the  difficulty,  and  at  times  impossibility,  of  so  doing  in  case  of  deep 
outs  or  fills  or  the  building  of  the  road  in  a new  location  is  apparent.  Good 
side  roads  are  difficult  to  find,  and  even  whan  they  do  exist  the  length  of  haul 
is  generally  increased  quite  materially.  The  effect  of  hauling  material  over  the 
finished  grade,  especially  in  case  of  wet  weather,  needs  no  comment.  Not  only  is 
the  placing  of  concrete  delayed  when  either  of  the  foregoing  methods  of  haulage 
is  employed,  but  when  concreting  is  finally  started  the  most  expensive  part  of  the 
work,  the  long  haul  part,  is  done  first.  This  results  in  small  payments  from  the 
state, at  a time  when  working  capital  is  most  badly  needed.  The  untrained  organiza- 
tion is  also  required  to  do  the  most  difficult  part  of  the  work  first. 

The  latest  and  most  modern  method  of  building  roads  on  a large  scale,  is 
by  means  of  the  li^ht  railway  method.  In  this  method  a light  railway  is  employed 
to  haul  material  in  batch  boxes  from  the  material  yard  directly  to  the  mixer.  Two 
batch  boxes  are  generally  oarried  on  each  car,  each  box  containing  complete  ma- 
terials for  a batch  of  proper  size  for  the  mixer.  On  arrival  at  the  mixer  each 
box  is  picked  up  by  means  of  a small  derrick  attached  to  the  mixer,  and  the  batch 
boxes  dumped  directly  into  the  skip.  With  this  system  materials  never  touch  the 
subgrade  at  all. 


DIRECT  CHARGING  OF  MIXER  BY  MEANS  OF  LIGHT  BAIL?/ AT. 


. 

. 

* - 


♦ 


7 


if 


In  place  of  the  wheeling  and  shoveling  gang  of  16  or  more  men  necessary 
in  the  old  method  of  'building  roads,  only  2 or  3 men  are  needed  to  charge  the 
mixer  by  means  of  the  hatch  hox  and  light  railway  system.  The  resulting  economy 
of  13  or  14  men,  at  the  present  high  price  of  labor,  amounts  to  a large  sum  in 
the  course  of  a season.  Due  to  the  fact  that  aggregates  are  not  dumped  on  the 
subgrade,  loss  of  material  and  the  picking  up  of  dirt  is  eliminated.  Minimum  de- 
lay from  rain  i6  insured,  while  it  is  possible  to  start  work  earlier  in  the  spring 
than  if  a method  of  construction  is  used  which  depends  upon  haulage  over  earth 
roads.  The  unobstructed  subgrade  permits  machine  trimming  to  be  performed,  thus 
reducing  the  cost  of  trimming  and  eliminating  loss  due  to  the  placing  of  extra 
concrete  resulting  from  inaccurate  subgrade. 


MACHINE  TRIMMING  OF  THE  SUBGRADE 


Light  railway  haulage  permits  the  laying  of  concrete  to  begin  at  the 
point  nearest  the  material  yard,  inasmuch  as  hauling  oan  be  performed  past  the 
uncured  concrete  on  the  shoulder  of  the  road.  The  laying  of  concrete  oan  begin 
as  soon  as  a few  hundred  feet  of  subgrade  have  been  prepared,  and  can  follow 
inmediately  behind  the  grading  operations  without  interference.  This  eliminates 
the  delay  that  generally  occurs  in  placing  concrete  when  a system  of  haulage  is 
used  which  cannot  operate  past  the  uncured  concrete.  Not  only  oan  the  placing  of 
concrete  and  the  operation  of  grading  be  carried  on  simultaneously,  but  the  most 
profitable  portion  of  the  conorete,  the  short  haul  portion,  is  done  first.  A 
large  payment  from  the  State  early  in  the  life  of  the  job  is  thus  insured,  provid- 
ing the  working  capital  generally  so  badly  needed  at  this  time.  Furthermore,  by 
the  time  the  long  haul  portion  of  the  job  is  reached,  the  organization  is  exper- 
ienced and  the  track  is  well  bedded. 


Another  method  of  construction  which  has  come  into  quite  general  use 
during  the  past  2 years,  is  to  haul  properly  proportioned  batches  in  motor  trucks 
and  dump  directly  into  the  skip  of  the  mixer.  Dump  body  trucks  of  3 and  5 ton 
capacity,  with  the  bodies  partitioned  off  so  as  to  form  compartments  for  a number 
of  batches,  are  sometimes  used.  The  difficulty  of  handling  these  heavy  units  on 
the  subgrade,  particularly  of  turning  them,  and  their  destructive  effect  on  the 
subgrade,  has  led  to  the  use  of  light  trucks,  such  as  the  Ford.  These  light  trucks 
are  equipped  with  oversize  tires,  and  with  special  dump  bodies  arranged  to  dump 
to  the  rear.  A number  of  patented  types  of  dump  bodies  are  on  the  market  at  the 


present  time,  among  than  the  Lee  body  and  the  Hanson  body.  The  Ford  truck 


8 


possesses  the  advantage  of  being  easily  turned  by  means  of  a light  turntable,  and 
of  not  cutting  up  the  subgrade  as  badly  as  the  larger  truck.  The  disadvantage  of 
the  light  truck  system  over  the  heavy  truck  system  is  the  larger  number  of  units 
and  drivers  required,  as  well  as  the  rapid  depreciation  of  the  light  machines* 

The  objection  to  all  truck  systems  is  the  delay  caused  by  wet  subgrade,  the  cut- 
ting up  of  the  subgrade,and  the  fact  that  the  placing  of  concrete  must  begin  at 
the  point  farthest  from  the  material  yard*  As  mentioned  in  a previous  paragraph 
this  results  in  considerable  delay,  and  in  minimum  payments  from  the  State  just 
at  a time  when  money  is  most  badly  needed. 


CHARGING  MIXER  DIRECT  FROM  TRUCK 


MOTOR  TRUCKS  HAULING  MIXED  CONCRETE 

In  some  parts  of  the  country  the  central  mixing  plant  method  of  building 
roads  has  been  used  to  a certain  extent.  When  this  method  is  employed,  the  mixed 
concrete  is  generally  hauled  out  to  the  road  by  neans  of  motor  trucks,  as  shown  in 


9 


the  above  photograph.  The  trucks  shown  in  the  photograph  are  5 ton  units,  hauling 
about  2 cubic  yards  of  concrete  per  trip  in  a special  dump  body.  The  difficulty 
of  removing  the  concrete,  and  the  planks  on  the  subgrade  necessary  to  prevent 
ratting,  are  clearly  shown.  Considerable  segregation  of  the  concrete  occurs, 
especially  if  the  consistency  is  wet.  The  use  of  a mechanical  finishing  machine, 
shown  in  the  lower  right  hand  corner  of  the  photcgraph,  permits  a dryer  consist- 
ency to  be  used,  and  obviates  to  a certain  extent  the  objections  to  the  central 
mixing  plant  nethod.  In  the  central  mixing  plait  method  there  is  always  the 
danger  that  too  great  a length  of  time  will  elapse  between  the  mixing  of  the  con- 
crete and  the  plaoing  of  it  on  the  road.  With  this  method  it  is  also  necessary 
to  delay  the  placing  of  concrete  until  a good  deal  of  the  grading  has  been  com- 
pleted, ani  to  begin  the  placing  of  concrete  at  a point  farthest  from  the  material 
yard.  The  possibility  of  delay,  due  to  wet  subgrade  and  the  cutting  up  of  the 
subgrade  by  the  motor  trucks,  is  another  objection  to  the  central  mixing  plant 
plan. 

The  central  mixing  plant  method  of  construction  has  been  used  in  a few 
instances  with  the  light  railway  system  of  batch  box  haulage.  The  mixed  concrete 
has  been  discharged  directly  into  batch  boxes  of  the  steel,  tip-over  type,  and 
hauled  to  the  road  in  the  regular  manner.  A crane  picked  up  the  loaded  boxes 
frcjn  the  cars  and  swung  them  over  the  subgrade  where  they  were  dumped  by  2 men. 

In  order  to  remove  the  packed  concrete  from  the  corners,  a small  air  compressor 
was  installed  on  the  crane.  The  photograph  below  shows  the  method  of  dislodging 
concrete  from  the  corners  of  the  box  by  means  of  thfr  compressed  air,  method.  A 
pressure  of  50  to  60  pounds  per  square  inch  has  been  found  sufficient.  The  same 
objection  to  the  segregation  of  the  concrete  and  the  possibility  of  too  long  a 
time  elapsing  between  the  mixing  and  finishing  operations,  can  be  brought  against 
the  central  mixing  plant  when  light  railway  haulage  is  enployed  as  when  motor 
truck  haulage  is  used. 


LIGHT  RAILWAY  HAULING  MIXED  COT  CRETE 


In  the  opinion  of  many  oontraotors,  aside  from  reliability  of  operation 
due  to  greater  independence  of  weather  conditions  and  the  saving  in  labor,  the 
biggest  advantage  of  light  railway  haulage  is  the  possibility  of  carrying  on  con- 
creting and  grading  operations  simultaneously.  This  insures  a large  payment  early 
in  the  life  of  the  job,  which  provides  much  needed  working  capital. 


10 


Until  the  summer  of  1919  hand  methods  were  universally  enployed  in 
striking  off  and  finishing  concrete  road,  and  concrete  base  for  other  types  of 
pavement.  At  that  time  the  first  successful  mechanical  finishing  machine,  that 
of  The  Lakewood  Engineering  Company,  of  Cleveland,  Ohio,  was  introduced,  and  at 
the  present  time  between  400  and  500  of  these  machines  are  in  use.  This  machine 
not  only  strikes  off  the  concrete,  but  subjeots  it  to  an  intensive  tamping  action. 
Dryer  mixtures  oan  thus  be  used,  resulting  in  denser  and  stronger  concrete  accord- 
ing to  the  researches  of  Professor  Duff  Abrams,  of  Lewis  Institute,  Chioago.  Hot 
only  does  the  mechanical  finishing  machine  produce  a better  pavement  but  it  saves 
the  labor  of  2 or  3 men  for  the  contractor.  A number  of  State  Highway  Departments 
at  the  present  time  either  specify  machine  finishing  for  concrete  roads,  or  offer 
special  concessions  to  the  contractor  to  induce  him  to  use  a finishing  machine. 


The  finishing  machine  shown  in  the  foregoing  illustration  is  well  adapted 
to  the  construction  of  brick  pavements,  especially  of  the  monolithic  type.  It  is 
employed  to.  strike  off  and  tamp  the  concrete  base  and  to  tamp  the  brick,  thus  pro- 
ducing a much  smoother  job  than  is  possible  by  hand  methods.  In  speaking  of  the 
use  of  the  finishing  machine  in  monolithic  brick  road  construct  ion  in  Engineering 
Hews-Record  for  January  6,  1921,  Mr,  W.  M.  Watson,  State  Highway  Engineer  of  Kansas, 
states  as  follows: 

I "At  the  beginning  of  the  work  the  base  was  poured  at  a stiff  con- 

sistency and  sbruok  off  by  the  Parrish  type  of  multiple  steel 
templet,  using  a 3/l6"  dry  sand-cement  bed.  The  brick  were  laid 
directly  on  the  sand-cement  bed  before  the  base  attained  its 
initial  set.  The  gravel  aggregate,  containing  very  little  coarse 
material,  produced  a concrete  with  which  it  was  difficult  to 
obtain  satisfactory  results.  When  mixed  sufficiently  dry  to 
permit  the  other  operations  it  contained  too  little  water  properly 
to  saturate  the  dry  cushion,  with  a consequent  separation  between 
the  base  and  brick  surface.  When  made  with  enough  water  to  give 
the  dry  cushion  the  proper  amount  of  water,  due  to  the  absence  of 
coarse  material,  the  concrete  had  little  stability,  rendering  the 
operations  of  rolling  and  grouting  exceedingly  difficult  and 


.. 


11 


making  it  almost  impossible  to  secure  a smooth  surface. 

This  trouble  has  been  overcome  by  the  use  of  a mechanical 
tamping  machine  operated  directly  on  the  base,  and  by 
eliminating  the  sand-cement  cushion.  A marked  improvement 
is  noted  by  reason  of  this  change,  not  only  in  the  surface 
of  the  pavement  but  in  the  adhesion  as  well.  Not  only 
does  mortar  tamped  to  the  surface,  firmly  adhere  to  the 
brick,  but  from  l/4"  to  l/2”  of  mortar  squeezes  up  be- 
tween the  bricks,  giving  greater  assured  resistance  to  the 
sliding  of  the  brick  along  the  base,  due  to  difference  in 
coefficient  of  expansion.  A much  denser  concrete  in  the 
base  is  also  assured.” 

Complete  specifications  of  the  Lakewood  finishing  machine  will  be  found 
in  the  appendix  to  this  thesis.  To  secure  the  best  results  with  a finishing  ma- 
chine it  is  necessary  to  use  steel  forms  weighing  not  less  than  6-l/2  pounds  per 
foot  exclusive  of  fastenings. 

A machine  for  trimming  subgrade  has  been  developed  by  The  Lakewood  Eng- 
ineering Company  and  is  now  extensively  used.  This  machine  operates  on  the  side 
fonns  and  is  generally  pulled  by  means  of  the  road  roller,  as  shown  in  the  follow- 
ing illustration. 


LAKEWOOD  SUBGRADER 


One  of  the  most  troublesome  and  expensive  operations  performed  in  road 
building  is  that  of  trimming  the  subgrade,  aid  by  hand  methods  it  is  seldom  possi- 
ble to  secure  a surface  closer  than  one-fourth  inch  of  the  correct  contour  and 
elevation.  With  the  rigid  inspection  characteristic  of  road  building  today,  the 
subgrade  is  generally  cut  too  low.  Loss  due  to  low  subgrade  is  one  of  the  most 
prevalent  and  difficult  to  overcome  when  subgrade  is  trinmed  by  hand.  Machine 
trimming  will  produce  a subgrade  practically  as  accurate  as  the  finished  pavemmt. 
When  we  stop  to  consider  that  a subgrade  one -fourth  inch  too  low  results  in  placing 
75  cubic  yards  of  oonorete  per  mile  of  18  foot  road  for  which  no  pay  is  received, 
and  oonorete  is  worth  from  $15.00  to  $22.00  per  cubic  yard,  the  possibility  of  loss 
from  this  source  is  apparent.  Machine  trinming  of  the  subgrade  not  only  results  in 
greater  accuracy,  but  in  less  cost  than  hand  trimming. 


. 


12 


In  the  past  hut  little  attention  has  been  paid  to  the  problem  of  in- 
suring a reliable  and  adequate  water  supply,  in  spite  of  the  fact  that  the  cost 
of  a good  pump  is  but  a few  per  cent  of  the  cost  of  the  plant,  whose  operation 
depends  entirely  on  it*  Happily  the  importance  of  insuring  a proper  water  supply 
is  now  fully  realized  by  progressive  highway  contractors,  many  of  whom  are  using 
a double  unit  pump*  The  double  unit  pump  consists  of  2 complete  pumps  and  gaso- 
lene engines  mounted  on  a truck,  so  arranged  that  either  pump  can  be  operated  in- 
dependently of  the  other  or  both  pumps  together  if  desired* 

The  use  of  a pipe  line  of  inadequate  capacity  is  one  of  the  most  expen- 
sive mistakes  which  a highway  contractor  can  make,  for  this  will  off-set  any  pro- 
vision he  has  made  for  adequate  pumping  capacity.  A pipe  line  not  less  than  2 
inches  in  diameter  should  be  used  to  furnish  water  for  a half  yard  or  three- quart ex 
yard  paving  mixer,  wet  batch  rating,  and  a pipe  line  preferably  of  2-l/2  inches 
diameter  for  a cubic  yard  mixer*  Gate  valves  should  be  provided  every  half  mile, 
and  unions  every  1,000  feet*  Provision  must  be  made  for  taking  care  of  expansion 
and  contraction  in  the  pipe  line,  either  by  means  of  a patented  expansion  joint 
such  as  that  manufactured  by  the  C.  H.  & E.  Manufacturing  Company,  of  Milwaukee, 
Wisconsin,  or  by  means  of  a home  made  device  consisting  of  a short  section  of  hose* 
Tees  should  be  inserted  in  the  pipe  line  approximately  every  100  feet  to  permit 
attachment  of  the  hose  leading  to  the  paving  mixer.  While  we  are  considering  the 
subject  of  pipe  lines,  it  is  desired  to  point  out  that  a oentral  mixing  plant  will 
not  eliminate  the  necessity  for  employing  a pipe  line  and  pump  because  water  must 
be  supplied  for  curing  the  concrete* 


To  supply  water  for  a half  yard  or  three-quarter  yard  paving  mixer  plant 
including  water  for  sprinkling  the  subgrade  and  curing  the  concrete,  the  pump 
should  be  capable  of  delivering  a supply  of  at  least  30  to  40  gallons  per  minute 
at  the  end  of  the  pipe  line*  In  order  to  supply  this  amount  at  the  end  of  3 miles 
of  new  2 inch  wrought  iron  pipe,  a pressure  of  about  225  pounds  per  square  inch 
must  be  maintained  at  the  pump  in  level  country* 


We  can  sum  up  the  modern  method  of  road  building  briefly  by  stating  that 
the  tendency  is  to  replace  hand  methods  by  machine  methods  wherever  possible* 

This  machinery  is  of  a much  better  type  than  that  formerly  considered  good  enough 
for  construction  work,  and  the  units  are  not  selected  in  a haphazard  fashion*  The 
modern  road  building  plant  consists  of  a number  of  high  class,  properly  balanced, 
and  coordinated  units,  designed  to  operate  as  a whole*  Boad  building  is  rapidly- 
becoming  a highly  oxganized  manufacturing  "business,  for  after  all  a road  builder 
is  a manufacture  assembling  his  raw  materials  into  the  finished  product  thru  the 
medium  of  machinery*  The  business  of  road  building  is  rapidly  assuming  the  highly 
organized  methods  of  the  manufacturer* 


13 


CHAPTER  III. 


RATE  OF  CONSTRUCTION 


The  rate  of  construction  obviously  depends  upon  the  type  of  road,  and 
upon  the  quantity  of  material  contained  in  it.  This  brings  us  to  the  considera- 
tion of  a mistake  frequently  made  in  computing  quantities  of  material,  namely 
assuming  the  average  thickness  of  a road  with  a crowned  surface  on  a flat  sub- 
grade to  be  the  mean  between  the  side  and  center  thickness.  If  the  surface  of  a 
road  is  a plane  this  assumption  would  be  correct,  but  the  surface  is  generally 
parabolic  or  cylindrical.  Due  to  the  long  radius,  there  is  practically  no  differ- 
ence in  the  average  thickness  of  a road  having  a cylindrical  or  a parabolic  sur- 
face. Assuming  the  surface  to  be  parabolic,  a formula  can  be  derived  for  the 
average  thickness.  This  formula  can  be  expressed  in  terms  of  the  mean  of  the 
side  and  center  depths,  plus  one-sixth  of  the  crown.  For  instance,  a road  6 
inches  thick  at  the  sides  and  8 inches  at  the  center  on  a flat  subgrade  has  an 
average  depth  of  7-l/3  inches.  In  case  the  subgrade  is  crowned  in  a different 
manner  from  the  surface  of  the  pavement,  the  average  thickness  is  equal  to  the 
mean  between  the  side  and  center  depths  plus  one-sixth  of  the  difference  between 
the  surface  and  subgrade  crowns.  Inasmuch  as  an  increase  of  l/s  inch  in  the 
average  depth  amounts  to  almost  100  cubic  yards  of  concrete  per  mile  of  18  foot 
road,  the  seriousness  of  assuming  the  average  depth  as  a mean  between  the  sides 
and  the  center  is  apparent. 


A road  6 inches  thick  at  the  sides  and  8 inches  thick  at  the  center  on 
a flat  subgrade  has  an  average  thickness  of  7-l/3  inches,  as  shown  in  the  preced- 
ing paragraph.  On  such  a road  1 cubic  yard  of  concrete  will  produoe  4.91  square 
yards  of  pavement.  An  18  foot  road  of  this  type  contains  0.407  cubic  yards  of 
concrete  per  lineal  foot,  or  2,150  cubic  yards  per  mile. 

Based  upon  a weight  of  376  pounds  per  barrel  of  cement,  3,000  pounds  per 
cubic  yard  of  sand,  and  2,700  pounds  per  oubic  yard  of  stone,  the  quantity  of 
material  required  per  mile  of  18  foot  concrete  road  of  a 1-2-3  mixture,  6 inches 
thick  at  the  sides  and  8 inches  thick  at  the  center,  is  as  follows: 


3,762  bbls.  cement  or 
1,118  cu.yds.  sand  or 
1,677  cu.yds.  stone  or 


707  tons 
1,677  " 

2.264  " 


Total  4,648  tons 


The  rate  of  construction  naturally  depends  to  a certain  extent  upon  the 
size  of  batch  used  in  the  concrete  mixer,  but  more  upon  the  efficiency  of  the 
organization.  Practically  all  state  highway  specifications  set  a time  limit  of 
not  less  than  1 minute  for  mixing  concrete,  and  this  time  limit  is  the  big  factor 
to  consider  in  determining  output.  When  a time  limit  of  1 minute  is  specified  it 
is  possible  for  a good  organization  to  produoe  40  batches  of  concrete  per  hour 
with  a one-half  or  three-quarter  yard  paving  mixer  without  violating  specifications 
Experience  indicates,  however,  that  30  batches  per  hour  is  a good  rate  of  opera- 
tion for  this  size  of  mixer,  and  a good  organization  with  an  adequate  supply  Of 
materials  should  maintain  this  rate.  With  a 1 cubic  yard  paving  mixer  it  is  not 
wise  to  count  on  more  than  24  batohes  per  hour.  It  must  be  clearly  understood 
that  the  rate  of  operation  given  in  this  paragraph  is  the  actual  rate  which  should 
be  obtained  under  normal  conditions,  and  is  not  inclusive  of  unusual  delays. 


♦ 


14, 


In  order  to  overcome  the  confusion  which  existed  a few  years  ago  with 
respect  to  the  capacity  of  concrete  mixers,  the  National  Association  of  Mixer 
Manufacturers  have  adopted  a standard  system  for  designating  the  capacity  of 
mixers*  At  the  present  time  a system  of  numbers  and  letters  is  used  which  indicate 
not  only  the  capacity  of  the  mixer,  but  also  the  type.  The  numbers  indicate  the 
cubic  feet  of  mixed  concrete  which  a mixer  can  handle  per  batch  under  normal  condi- 
tions, while  the  letters  indicate  whether  the  mixer  is  a side  loader  and  side  dis- 
charge machine  or  an  end  loader  and  end  discharge  machine.  The  side  loading  and 
side  discharge  machines  are  building  mixers,  while  the  end  loading  and  end  dis- 
charge machines  are  paving  mixers.  For  instance,  a 14-E  mixer  indicates  a paving 
mixer,  having  a capacity  of  14  cubic  feet  of  mixed  concrete  per  batch,  while  the 
21-S  mixer  indicates  a building  mixer  having  a capacity  of  21  cubic  feet  of  con- 
crete per  batch.  The  amount  of  dry  materials  required  to  produce  a certain  amount 
of  mixed  concrete,  is  approximately  50  per  cent  greater  than  the  volume  of  the 
mixed  concrete. 

At  the  present  time  the  tendency  is  toward  the  use  of  larger  paving 
mixers,  for  a large  machine  can  be  operated  with  practically  no  more  men  than  a 
small  machine.  The  10-E,  14-E,  and  21-E  machines  are  the  types  most  commonly  em- 
ployed in  highway  construction  at  the  present  time.  The  2F-E  machine  is  rapidly 
coming  into  favor,  however,  and  promises  to  become  the  most  popular  type  within  a 
few  years.  The  10-E  machine  is  entirely  too  small  for  quantity  production  of  roads 
and  the  manufacture  of  this  type  has  now  been  discontinued  by  most  manufacturers. 
The  14-E  and  21-E  sizes  are  employed  on  perhaps  95  per  cent  of  the  work  today. 

The  size  of  a batch  of  concrete  is  generally  expressed  in  terms  of  the 
number  of  bags  of  cement  which  it  contains,  such  as  a 3 bag  or  4 bag  batch.  Nat- 
urally the  number  of  bags  of  cement  which  can  be  placed  in  one  batch  depends  upon 
the  capacity  of  the  mixer, and  the  proportions.  For  instance,  a 14-E  mixer  can  be 
used  to  mix  a 4 bag  batch  of  1-2-3  concrete,  producing  15«£  cubic  feet,  inasmuch 
as  all  mixers  are  designed  with  a normal  overload  capacity.  To  mix  a 5 bag  batch 
of  1-2-3  concrete,  amounting  to  19.5  cubic  feet,  will  require  a 21-E  mixer.  A 
28-E  mixer  is  capable  of  mixing  a 7 ba£  batch  of  this  mixture.  On  the  other  hand 
if  the  concrete  is  to  be  mixed  in  the  proportions  of  l-2§^5,  a 14-E  mixer  can 
handle  only  a 3 bag  batoh,  etc. 

At  a rate  of  30  batches  per  hour,  a 14-E  mixer  handling  a 4 bag  batch  of 
1-2-3  concrete  will  produce  17.4  cubic  yards.  At  this  rate  the  output  in  10  hours 
would  be  174  oubic  yards,  equivalaat  to  854  square  yards  of  concrete  averaging 
7-l/3  inches  in  thickness.  Such  an  output  is  equivalent  to  427  lineal  feet  of 
18  foot  road.  To  allow  for  minor  delays  we  will  call  the  daily  output  400  feet 
of  road  of  this  type. 

In  estimating  the  monthly  output  it  is  not  wise  to  assume  more  than  20 
working  days  per  month  during  a normal  season.  At  a rate  of  400  feet  of  road  per 
day,  a 14-E  mixer  should  produce  8,000  feet  or  l-l/2  miles  per  20  day  month.  To 
allow  further  for  contingencies,  experience  indicates  that  the  monthly  output  of 
a 14-E  mixer  on  the  type  of  road  we  have  assumed  should  not  be  taken  to  exceed 
l-l/4  miles  under  normal  conditions.  Sometimes  it  is  wise  not  to  count  on  more 
than  1 mile  of  18  foot  concrete  road, having  an  average  thickness  of  7-l/3  inches, 
per  month  from  a 14-E  machine.  These  outputs  are  based  upon  normal  conditions, 
and  might  be  materially  altered  one  way  or  the  other  by  weather  conditions,  mater- 
ial supply,  etc.  Local  conditions  must  be  considered  and  individual  judgment 
exercised  in  estimating  the  probable  rate  of  construction  on  any  job,  but  a good 
organization  with  an  adequate  supply  of  materials  should  produce  the  outputs 
mentioned  in  this  paragraph. 


% 


15 


The  amount  of  road  produced  per  season  depends  largely  upon  the  length 
of  the  working  season,  which  in  turn  varies  with  climatic  conditions.  In  the 
Middle  West  a working  season  of  5 or  6 months  is  all  that  can  he  depended  upon, 
while  in  California  and  parts  of  the  South  the  working  season  is  frequently  twice 
as  long.  With  a working  season  of  5 or  6 months  a good  organization  with  an  ade- 
quate supply  of  materials  should  produce  from  6 to  7-jjr  miles  of  standard  18 “foot 
concrete  road  under  normal  conditions  with  a 14-E  mixer.  A 21-E  mixer  should  pro- 
duce from  8 to  9 miles  of  standard  concrete  road  in  a normal  season,  while  a 28-E 
mixer  should  produce  from  10  to  12  miles.  A standard  concrete  road  is  considered 
to  he  18  feet  wide,  with  an  average  thickness  of  7-l/3  inches. 

The  output  of  road  per  working  season  depends  upon  many  factors  other 
than  the  capacity  of  the  mixer,  chief  among  whioh  are  the  organizing  ability  of 
the  contractor  and  the  supply  of  raw  materials.  Many  cases  are  known  where  a 14-E 
paving  mixer  is  producing  only  250  lineal  feet  of  18  foot  concrete  per  10  hour 
day,  whereas  the  same  type  of  machine  working  under  practically  the  same  conditions 
a few  miles  away  is  producing  from  400  to  500  feet.  It  is  true  that  during  the 
past  two  years  the  output  of  road  has  been  seriously  limited  by  the  shortage  of  raw 
material,  and  by  erratic  and  inefficient  railroad  service.  Nevertheless  the 
biggest  limiting  factor  in  road  production  has  always  been,  and  still  is,  poor 
organization.  Some  men  will  take  a second  hand  concrete  mixer  and  a few  wheel- 
barrows and  make  a success  of  highway  construction,  while  others  will  fail  even 
though  equipped  with  the  most  modern  machinery.  In  highway  construction,  as  in 
every  other  human  activity,  the  personal  element  enters  largely  into  the  final 
result  s • 

To  show  the  possibility  of  producing  roads  in  quantity,  a few  examples 
selected  at  random  from  various  sections  of  the  country  will  be  given: 

In  1919  the  Bates  & Bogers  Construction  Company,  of  Chicago,  averaged 
440  lineal  feet  of  standard  Illinois  18  foot  concrete  road  per  day  for  3 weeks 
with  a 14-E  mixer  in  one  run.  On  another  occasion  they  averaged  better  than  460 
feet  per  day  for  10  days.  These  performances  were  given  me  during  a conversation 
with  a member  of  the  firm,  and  undoubtedly  they  were  duplicated  or  exoeeded  many 
times.  In  1920  this  same  firm  laid  as  high  as  490  feet  of  concrete  road  17  feet 
4 inches  wide  averaging  9-l/3  inches  in  thickness  in  10  hours  with  a 14-E  mixer 
for  the  Ohio  State  Highway  Department, 

In  1920  and  1921  Twohy  Brothers,  of  Portland,  Oregon,  operating  on  a 268 
mile  concrete  road  contract  in  Arizona,  frequently  placed  500  feet  of  18  foot  con- 
crete road  of  a 1-2-4  mix  and  7-l/3  inch  average  thickness  in  8 hours.  A 14-E 
Lakewood  paving  mixer  was  used,  supplied  with  a light  railway  haulage  system.  The 
photograph  on  page  6 shows  one  of  the  mixing  plants  on  this  job.  Note  the  small 
organization  required  to  operate  this  plant. 

Allen  J.  Parrish,  of  Paris,  Illinois,  in  1920,  produced  as  high  as  790 
feet  of  standard  Illinois  18  foot  concrete  road  with  a 21-E  Smith  paving  mixer  in 
10  hours.  His  average  output  for  14  consecutive  working  days  was  565  feet,  while 
his  output  thruout  the  season  averaged  well  over  450  feet  per  working  day.  Mr. 
Parish  used  a 5 bag  batch  of  1-2-3^-  concrete,  and  in  order  to  produce  790  feet  of 
road  in  10  hours  it  was  necessary  to  maintain  an  output  of  about  40  batches  per 
hour  thruout  the  day.  In  speaking  of  Mr.  Parrish’s  accomplishment  Engineering 
News-Record  for  January  6,  19211states  as  follows:  "Explanation  of  this  continuous 
good  progress  lies  in  the  one  word  managemait,  which  includes  keeping  the  supply  of 
materials  constant." 


16. 


Johnson,  Drake  & Piper,  of  Minneapolis,  built  an  average  of  590  lineal 
feet  of  18  foot  concrete  road  for  23  days  in  the  month  of  October,  1920.  The 
total  output  for  the  month  amounted  to  2.37  miles.  This  was  accomplished  by 
hauling  out  properly  proportioned  batches  in  trucks,  and  d imping  directly  into  the 
skip  of  the  1 cubic  yard  mixer.  The  type  of  road  was  concrete  18  feet  wide,  of  a 
1-2-4  mixture,  and  an  average  thickness  of  7-l/3  inches. 

Siams,  Helmer,  & Schaffner,  of  St.  Paul  on  state  road  wDrk  in  Minnesota, 
have  produced  as  much  as  1,072  lineal  feet  of  18  foot  concrete  road  in  10  hours. 
Properly  proportioned  batches  were  hauled  out  in  batch  boxes  by  means  of  light 
railway,  and  were  dumped  directly  into  a specially  arranged  28-S  Lakewood  building 
mixer.  This  work  was  performed  during  the  season  of  1920. 

Another  Minnesota  firm,  McCree-Moos,  of  St.  Paul,  laid  1,098  feet  of 
18  foot  concrete  road  in  10  hours  during  the  season  of  1920.  A central  mixing 
plant  consisting  of  a 1 cubic  yard  building  mixer  was  used  to  mix  the  concrete, 
which  was  hauled  to  the  road  by  means  of  motor  trucks. 

Mr.  G.  P.  Scharl,  of  Muskegon,  Michigan,  operating  a 28-E  Koehring  mixer 
supplied  by  means  of  the  light  railway  and  batch  box  system,  has  produced  1,031 
lineal  feet  of  18  foot  concrete  road  in  10  hours.  This  road  was  18  feet  wide,  of 
a l-l^-3  mixture,  and  an  average  thickness  of  7-l/3  inches.  Mr.  Scharl' s best 
weekly  output  was  somewhat  over  5,000  feet,  while  his  monthly  output  has  run  as 
high  as  2-l/2  miles.  This  work  was  performed  in  1920. 

The  Henry  W.  Horst  Company,  of  Rock  Island,  Illinois,  operating  on 
standard  Illinois  concrete  road  16  and  18  feet  wide  near  Vandalia,  Illinois,  dur- 
ing the  season  of  1920,  frequently  laid  600  feet  of  road  in  10  hours.  Mr.  Horst 
used  Ford  trucks  to  haul  properly  proportioned  batches  and  dump  directly  into  the 
skip  of  the  paving  mixer.  A central  mixing  plant  was  also  used  in  conjunction 
with  Ford  trucks,  and  the  output  of  each  method  was  just  about  the  same. 

James  0.  Heyworth,  of  Chicago,  in  building  an  18  foot  concrete  road  for 
the  Illinois  State  Highway  Department , during  the  seasons  of  1919  and  1920,  fre- 
quently laid  500  feet  in  10  hours  with  the  light  railway  system.  MellonrStuart, 
Nelson  Company,  of  Chicago,  operating  on  standard  18  foot  Illinois  concrete  road 
near  Desplaines,  Illinois,  laid  from  600  to  700  feet  of  road  in  10  hours.  A 
li^it  railway  system  manufactured  by  the  Western  Wheeled  Scraper  Company,  of  Aurora 
Illinois,  was  used  to  haul  properly  proportioned  batches  in  batch  boxes  to  the 
21-E  mixer. 

Thomas  Fitzgerald,  of  Ashtabula,  Ohio,  during  the  season  of  1919,  laid 
11.92  miles  of  monolithic  brick  road  16  and  18  feet  wide  in  92  working  days  for 
the  Ohio  State  Highway  Department,  with  two  14-E  mixers. 

George  Walters,  of  Butler,  Penna.  laid  from  525  feet  to  588  feet  of  16 
foot  reinforced  concrete  road  of  a 1-2-3  mixture  and  an  average  thickness  of 
7-l/3  inches, in  10  hours.  This  work  was  performed  in  the  summer  of  1920  for  the 
Pennsylvania  State  Highway  Department,  using  a 14-E  Rex  mixer.  The  minimum  time 
limit  in  Pennsylvania  for  mixing  concrete  is  l-l/4  minutes. 

The  Quinlan-Robertson  Company,  of  Montreal,  Canada,  in  1920  have  laid 
from  600  to  700  feet  of  standard  18  foot  Pennsylvania  reinforced  concrete  road  in 
10  hours.  A light  railway  haulage  system  was  used  to  haul  material  in  batch 
boxes  to  a 28-E  Koehring  paver. 


I 


♦ 


17 


Elder  & Company,  at  Georgetown,  Delaware,  laid  as  high  as  781  feet  of 
14  foot  concrete  road,  having  an  average  thickness  of  6-l/3  inches,  in  10  hours 
during  the  season  of  1920.  This  work  was  performed  for  the  Delaware  State  Highway 
Department.  A 28-E  Koehring  mixer  was  used  to  mix  the  concrete,  which  was  of 
1-2-4  proportions. 

The  Chicago  Heights  Coal  Company,  at  Momence,  Illinois,  and  the  J,  J. 
Dunnegan  Construction  Company,  at  Morrison,  Illinois,  have  produced  from  450  to 
550  lineal  feet  of  18  foot  standard  Illinois  concrete  road  in  10  hours,  during  the 
seasons  of  1919  and  1920.  The  light  railway  system  of  haulage  was  used  to  supply 
14— E Lakewood  paving  mixers. 

It  is  "by  no  means  intended  to  convey  the  impression  that  the  output 
of  road  mentioned  in  the  preceding  paragraphs  was  maintained  every  day  thruout  the 
season.  They  were  merely  mentioned  to  show  the  possibility  for  quantity  produc- 
tion open  to  a contractor  of  good  organizing  ability,  and  as  an  answer  to  those 
who  claim  that  from  250  to  300  feet  of  road  per  10  hour  day  is  all  that  can  be 
expected.  The  fact  that  the  records  mentioned  above  were  made  during  the  periods 
of  acute  material  and  labor  shortage  prevailing  in  1919  and  1920,  is  all  the  more 
reason  to  assume  that  these  records  will  not  only  be  frequently  duplicated  but 
greatly  exceeded  during  the  normal  times  which  seem  to  be  approaching.  As  in  the 
case  of  Mr.  Parrish,  the  explanation  of  the  foregoing  records  is  given  by  the 
one  word  management,  though  undoubtedly  a properly  balanced  and  coordinated  road 
building  plant  was  a oontributary  cause.  The  selection  of  the  proper  road  build- 
ing plant,  however,  can  also  be  considered  as  coming  under  the  head  of  good  manage- 
ment • 

Heretofore  contractors  have  paid  but  little  attention  to  the  problem  of 
insuring  an  adequate  supply  of  raw  materials  during  the  working  season,  by  storing 
material  during  the  inactive  months.  The  general  practice  has  been  to  depend  more 
or  less  upon  day  to  day  delivery  from  the  producer  and  the  railroad.  The  danger 
of  such  practioe  has  been  most  forcefully  presented  during  the  acute  material 
shortage  and  inefficient  and  erratic  railroad  service  prevailing  the  past  two  years^ 
A manufacturer  who  undertook  business  without  adequate  preparation  in  the  way  of 
stock  on  hand,  would  not  be  considered  a man  of  good  business  judgnent*  A con- 
tractor is  nothing  more  nor  less  than  a manufacturer  of  roads,  and  failure  on  his 
part  to  adequately  prepare  for  the  construction  season  by  storing  material  is  no 
more  excusable  than  it  would  be  on  the  part  of  the  manufacturer  of  any  other 
article.  State  highway  departments,  profiting  by  the  experience  of  the  past  two 
years,  now  realize  the  necessity  for  a contractor  preparing  himself  for  the  con- 
struction season  by  storing  material  during  the  winter  months.  In  the  past  the 
biggest  handicap  to  this  practice  has  been  the  large  amount  of  working  capital 
tied  up.  In  order  to  overcome  this  handicap  and  induce  contractors  to  store  mat- 
erial during  the  inactive  months,  most  states  have  made  provision  in  their  speci- 
fications for  monthly  payments  on  stored  material.  This  should  go  a long  way  to- 
ward inducing  contractors  to  store  material,  and  a resulting  decreased  delqy  dar- 
ing the  construction  season  should  mean  a greater  output  of  road. 

In  the  fall  of  1919  the  Lakewood  Engineering  Company,  of  Cleveland,  Ohio 
sent  letters  to  a large  number  of  material  producers  thruout  the  country,  asking 
them  their  opinion  of  winter  storage  of  materials.  Many  producers  replied  that 
it  would  be  impossible  or  very  difficult  to  operate  all  winter,  but  the  consensus 
of  opinion  of  about  100  producers  thruout  the  country  was  to  the  effect  that  they 
could  operate  at  least  2 or  3 months  longer  than  they  do  at  present  if  contractors 
would  store  material  during  the  inactive  months.  In  the  fall  of  1920  the  Lakewood 


. 


18 


Engineeriig  Company  again  sent  out  hundreds  of  letters  to  State  Highway  Depart- 
ments, Bankers,  Material  Producers,  Contractors  and  Railroad  Officials  on  the 
subject  of  winter  storage  of  road  building  material.  The  consensus  of  opinion 
from  all  classes  was  that  winter  storage  is  not  only  desirable  but  necessary  if 
the  production  of  roads  is  to  be  adequate  to  the  demands.  The  progressive  con- 
tractor, therefore,  who  desires  to  insure  himself  against  delay  during  the  con- 
struction season,  should  have  no  difficulty  at  the  present  time  in  financing  winter 
storage  of  materials.  It  is  realized  that  the  storage  of  materials  during  the  most 
severe  weather  in  many  parts  of  the  country  is  very  difficult,  but  it  is  almost 
always  possible  to  store  materials  for  a month  or  two  before  severe  winter  weather 
sets  in  and  for  the  same  length  of  time  in  the  early  spring  before  the  season  is 
sufficiently  advanced  to  permit  laying  concrete. 

The  storage  of  cement  is  much  more  difficult  than  the  storage  of  sand 
or  stone,  because  of  the  possibility  of  spoiling.  Many  states,  however,  will  per- 
mit canent  to  be  stored  after  a certain  date,  among  them  Pennsylvania  which  per- 
mits this  practice  after  February  15th.  Many  contractors  have  suffered  loss  in 
the  past  due  to  improper  storage  of  cement.  A good  discussion  of  this  subject 
appeared  in  Engineering  Hews -Record  for  December  2,  1920  by  Mr.  Blain  S.  Smith, 
General  Sales  Manager  for  the  Universal  Portland  Cement  Company,  of  Chicago.  In 
this  discussion  Mr.  Smith  pointed  out  that  not  only  should  the  cemait  shed  have 
weather  tight  walls,  floor  and  roof  lined  with  building  paper,  but  the  cement 
should  be  so  piled  as  to  prevent  the  circulation  of  air,  for  air  carries  moisture. 
In  order  to  prevent  circulation  of  air  it  is  wise  to  cover  the  cement  with  tuild- 
ing  paper  or  canvas.  If  the  precautions  recommended  by  Mr.  Smith  are  observed, 
a contractor  should  run  but  little  risk  in  storing  cement.  When  payments  are  made 
on  cement  by  State  Highway  Departments,  no  allowance  is  made  for  sacks.  Bulk 
cement  possesses  a big  advantage  in  this  respect,  because  a contractor  is  not 
called  upon  to  tie  up  his  money  at  the  rate  of  $1.00  per  barrel  for  the  non-pro- 
ductive item  of  sacks. 

Experience  during  the  past  two  years  has  shown  the  fallacy  of  awarding 
more  work  than  can  be  completed  in  one  season,  for  the  effect  of  this  practice  is 
to  create  a serious  material  shortage  and  to  delay  the  progress  of  all  contractors. 
Another  result  of  this  practice  is  to  cause  an  increase  in  contract  prices.  Con- 
tractors who  secure  the  work  late  in  the  season  can  thus  afford  to  pay  more  for 
material  and  labor  than  those  who  were  awarded  work  earlier  in  the  year,  to  the 
detriment  of  the  latter.  Based  upon  their  experience  during  the  past  two  years 
the  Pennsylvania  State  Highway  Department,  one  of  the  best  organized  in  the  country, 
has  concluded  that  about  500  miles  of  trunk  line  concrete  road  is  about  all  they 
can  expect  at  the  present  time  per  working  season.  It  is  quite  probable  of  course 
that  as  contractors  realize  more  fully  the  need  of  proper  preparation  for  the 
construction  season  by  storing  material  during  the  winter  months,  that  this  limit 
of  500  miles  per  year  will  be  considerably  increased,  until  the  Pennsylvania 
Department  is  convinced  that  conditions  have  changed  sufficiently,  they  intend  to 
limit  their  yearly  awards  to  500  miles  of  road.  The  standard  type  of  trunk  line 
road  in  Pennsylvania  is  reinforced  concrete  of  a 1-2-3  mixture,  18  feet  wide,  and 
of  an  average  thickness  of  7-l/3  inches.  A minimum  time  limit  of  l-l/4  minutes 
for  mixing  is  specified. 

In  the  introduction  to  this  thesis  an  estimate  was  given  of  the  probable 
length  of  time  required  to  complete  our  primary  highway  system  of  450,000  miles. 
This  estimate  was  based  upon  funds  available  of  $1,000,000,000,  and  an  average 
cost  of  $40,000  per  mile.  It  is  interesting  to  note  that  if  all  states  were  build- 
ing roads  at  the  rate  which  Pennsylvania  considers  proper,  that  this  would  result 


19 


in  an  output  of  24,000  miles  of  trunk  line  highway.  This  is  the  same  figure 
arrived  at  in  the  previous  estimate.  Even  allowing  for  increased  production  due 
to  improved  equipment,  improved  material  supply,  and  better  management  on  the  part 
of  contractors,  it  would  seem  that  an  output  of  24,000  miles  of  trunk  line  highway 
per  year  will  not  be  attained  for  some  time.  It  seems  reasonable  to  suppose, 
therefore,  that  at  least  20  years  are  necessary  for  the  construction  of  our  trunk 
line  system  of  450,000  miles. 

In  addition  to  encouraging  contractors  to  store  materials  during  the 
winter  months  by  paying  for  material  as  delivered.  State  Highway  Departments  can 
greatly  assist  in  increasing  the  production  of  roads  by  awarding  contracts  early 
and  in  large  sections*  The  use  of  li^it  railway  haulage  should  also  result  in  an 
increased  yearly  output,  because  work  oan  be  started  earlier  in  the  spring  than 
if  hauling  must  be  performed  over  earth  roads  and  the  delay  from  rain  should  be 
reduced  to  a minimum. 


the  final  analysis  the  output  of  roads  will  depend  upon  the  managing 
ability  of  the  contractor,  though  it  is  fully  realized  that  some  factors,  such  as 
poor  railroad  service,  are  largely  beyond  his  control.  Even  here,  however,  the 
good  manager  will  take  precautions  which  will  minimize  as  much  as  possible  delay 
from  this  source.  The  contractor  who  is  a good  manager  and  a good  organizer  will 
generally  secure  good  results  no  matter  what  method  or  what  type  of  equipment  he 
will  employ,  though  it  is  reasonable  to  suppose  he  will  secure  better  results  with 
some  methods  and  equipment  than  with  others.  The  contractor  who  is  a poor  manager 
on  the  other  hand  will  not  secure  good  results,  as  a rule,  no  matter  how  elaborate 
or  costly  his  equipment  may  be.  In  road  building, as  in  all  operations, the  human 
element  enters  largely  into  the  final  results. 


4 


% 


20 


CHAPTER  IV. 


THE  APPLICATION  OF  LIGHT  RAILWAY  TO  HIGHWAY  CONSTRUCTION. 


The  idea  of  using  light  railway  haulage  in  highway  construction  is  not 
a new  one  by  any  means , and  attempts  have  been  made  from  time  to  time  in  the  past 
to  use  this  method  of  haulage.  Until  two  years  ago,  however,  most  of  the 
attempts  to  use  light  railways  have  been  rather  unsuccessful  from  the  standpoint 
of  both  cost  and  operation.  This  was  due  principally  to  the  use  of  very  poor 
track,  and  rolling  stock  Intended  primarily  for  railroad  construction.  This 
equipment  was  too  heavy  and  inflexible  for  the  class  of  work  it  was  called  upon 
to  perform  in  road  building.  The  motive  power  consisted  of  four  wheeled  steam 
locomotives  weighing  from  12  to  20  tons.  These  heavy  machines  soon  warped  the 
light  track  so  badly  that  frequent  derailments  and  many  delays  were  caused.  A 
very  light  type  of  track  was  used  with  short, narrow,  open-end  corrugated  ties, 
and  rail  weighing  only  12  to  16  pounds  per  yard.  These  ties  did  not  have  suffi- 
cient bearing  area  to  support  the  heavy  concentrated  loads  imposed  by  the  loco- 
motives, nor  did  the  rail  possess  sufficient  beam  strength  to  carry  the  load  be- 
tween ties  without  warping.  The  rails  were  fastened  to  the  ties  by  means  of 
clips,  resulting  in  a track  of  but  little  rigidity.  The  photograph  below  illus- 
trates some  of  this  badly  warped  track. 


EFFECT  OF  HEAVY  ROLLING  STOCK  ON  LIGHT  TRACK 


Another  reason  for  lack  of  success  in  the  past  with  light  railway  haul- 
age, lay  in  the  use  of  V-body  dump  cars  and  paving  mixers  with  side  loading  skips. 
Unless  the  track  was  at  the  proper  elevation  and  location  with  respect  to  the 
loading  skip  it  was  very  difficult  to  dump  material  into  the  skip,  and  in  any 
event  it  was  generally  necessary  to  detail  several  men  to  scrape  the  cars  clean. 
The  space  required  by  these  side  loading  paving  mixers  was  so  great  that  it  was 
generally  necessary  to  straddle  one  of  the  side  forms,  while  the  foira  on  the  side 
next  to  the  track  could  only  be  placed  one  section  at  a time  as  the  mixer  moved. 


♦ 


21 


V-BODY  CARS  CHARGING  SIDE  -LOADING  PAVING  MIXER 


Some  years  ago  when  light  railway  haulage  was  first  thought  of  in 
connection  with  highway  construction,  material  was  frequently  dumped  on  the  sub- 
grade  in  long  windrows  in  the  same  manner  as  when  teams  or  trucks  were  used.  The 
possible  saving  of  labor  in  charging  the  mixer  directly  from  the  railway  cars  so 
as  to  eliminate  the  wheeling  and  shoveling  crew,  was  not  taken  advantage  of.  The 
railway  method,  therefore,  did  not  possess  any  advantages  over  any  other  method, 
as  far  as  labor  at  the  mixer  was  concerned.  The  sole  advantage  of  the  railway 
method  at  that  time  was  elimination  of  rutted  subgrade,  and  the  somewhat  more  or 
less  increased  reliability  of  operation  due  to  the  fact  that  haulage  could  be 
performed  in  spite  of  wet  roads.  Delays  from  derailment  were  so  frequent,  however, 
with  the  makeshift  equipment  used  that  increased  reliability  over  other  methods 
was  at  least  questionable,  while  the  investment  required  was  considerably  greater. 


DERAILMENT  RESULTING  FROM  POOR  TRACK  AND  EQUIPMENT 


22 


1 


The  old  ccnception  of  highway  construction  failed  to  recognize  the  fact 
that  hauling  is  hut  one  of  many  operations  performed  by  the  contractor,  though 
next  to  providing  an  adequate  supply  of  raw  material  it  is  the  most  important  one. 
But  even  so  the  cost  of  hauling,  alone,  is  not  the  proper  criterion  hy  which  to 
judge  the  merits  of  a plan  of  operation.  If  the  only  function  the  contractor  had 
to  perform  was  to  haul  material  from  one  point  to  another,  then  the  cost  of  haul- 
ing per  ton  mile  would  he  the  proper  criterion  to  use  in  judging  the  merits  of  a 

plan.  Any  method  of  operation  which  entails  unnecessary  labor  at  the  mixer,  on 
the  subgrade,  etc.  is  not  good,  even  though  the  cost  of  performing  one  of  the 
functions,  such  as  hauling,  is  low.  In  other  words  a road  building  plant  must  he 
considered  as  a whole,  and  it  must  he  judged  hy  its  performance  as  a unit  and  not 
simply  hy  the  performance  of  one  of  its  parts.  Failure  to  recognize  this  fact 
was  one  of  the  contributing  causes  to  the  lack:  of  success  which  characterized  early 
attempts  to  apply  light  railway  haulage  to  highway  construction. 

The  hack-hone  of  any  railway  system,  especially  a light  railway  system, 
is  the  traok.  It  is  possible  to  operate  poor  equipment  over  good  track  with 
success,  as  far  as  the  track  is  concerned,  hut  it  is  not  possible  to  operate  even 

the  best  of  equipment  over  poor  track  with  any  degree  of  success.  Not  only 

should  the  track  he  adequate  to  carry  the  loads  imposed  upon  it  without  permanent 
distortion,  hut  it  should  he  properly  laid  and  maintained  at  all  times.  Without 
proper  attention  to  laying  and  maintenance,  even  the  best  track  will  not  prove 
satisfactory.  Aside  from  the  fact  that  the  track  used  was  of  improper  design  and 
inadequate  capacity  to  carry  the  loads  imposed  upon  it,  failure  to  properly  lay 
and  maintain  it  was  one  of  the  big  causes  for  the  lack  of  success  which  attended 
early  attempts  to  apply  light  railway  haulage  to  highway  construction. 


OLD  STYLE  TRACK  OF  INADEQUATE  CAPACITY 


Track  sufficiently  heavy  to  carry  the  heavy  rolling  stock  employed  in  the 
past  was  sometimes  used,  and  gave  good  results  as  far  as  successful  operation  of 
the  trains  was  concerned.  The  cost  of  laying  and  removing  such  track  however,  was 
excessive  ;and  portability,  so  inqportant  in  an  operation  of  this  kind,  was  sacri- 
ficed. Wooden  ties  were  generally  used  in  this  type  of  track,  hut  after  the  track 
had  been  relaid  a few  times  the  ties  were  so  Mspike-outn  as  to  render  them  useless. 
A comparison  of  fabricated  and  wood -tie  track  is  inoluded  in  the  appendix. 


J 


23 


WOODEN  TIE  TRACK 


Prior  to  1918,  the  corrugated  type  of  tie  bolted  to  the  rail  was  almost 
universally  used  in  light  railway  track.  This  tie  was  rolled  by  steel  mills  as 
a standard  section,  and  was  simply  sawed  off  to  the  length  desired  for  use  in  the 
track.  As  a rule  the  ties  were  short,  with  only  a 2 inch  or  3 inch  projection 
beyond  the  rail.  This  resulted  in  "center- bound"  track,  because  of  the  insuffi- 
cient support  afforded  by  the  short  projection  of  the  tie.  The  ties  were  narrow, 
about  4 inches  to  4^-  inches  in  width,  and  the  open  ends  permitted  the  soil  to 
flow  when  saturated  with  moisture.  Sinking  of  the  track  resulted  when  the  ground 
was  at  all  soft,  so  it  was  necessary  to  place  planks  beneath  the  tie6  in  order  to 
secure  sufficient  bearing  area.  This  was  one  of  the  big  reasons  why  contractors 
in  the  past  looked  with  disfavor  upon  the  use  of  light  railway  haulage  in  highway 
construction. 


SOIL  FLOW  CAUSED  BY  OPEN  END  TIES 


24 


PLANKS  UNDER  TRACK  NECESSITATED  BY  INADEQUATE  TIES 


Bolting  of  the  ties  to  the  rail  resulted  in  a track  of  but  little 
rigidity.  The  rail  on  one  side  would  frequently  creep  ahead  of  the  rail  on  the 
other,  so  that  it  was  quite  difficult  to  replace  a section  or  insert  a switch# 

For  this  reason  it  was  frequently  necessary  to  saw  one  or  more  rails.  The  im- 
portance of  rigidity  in  track  construction  has  been  pointed  out  by  the  Joint 
Committee  on  Track  Stresses  of  the  American  Society  of  Civil  Engineers  and  the 
American  Railway  Association,  as  a result  of  their  researches  in  this  subject. 

A rigid  track  distributes  a load  over  a number  of  ties  on  each  side  of  the  one 
over  which  the  load  is  actually  placed.  In  a non-rigid  track,  however,  the  tie 
over  whioh  the  load  is  actually  placed  is  called  upon  to  carry  almost  all  of  the 
load,  inasmuch  as  it  receives  but  little  assistance  from  adjacent  ties.  In  non- 
rigid  track,  therefore,  heavy  concentrated  loads  are  liable  to  result  in  severe 
deformations. 

The  wide-spread  application  of  light  railway  to  military  operations 
during  the  World  War,  resulted  in  the  development  of  a pressed  steel  type  of  tie 
possessing  much  greater  bearing  area  than  the  old  type  of  corrugated  tie.  This 
type  of  tie  has  since  been  adopted  in  light  railway  track  applied  to  highway 
construction,  principally  by  The  Lakewood  Engineering  Company,  of  Cleveland,  Ohio. 
Instead  of  a projection  beyond  the  rail  of  only  2 or  3 inches,  the  pressed  steel 
tie  projects  some  7 or  8 inches.  The  ratio  of  tie  projection  to  the  gauge  of track 
in  the  pressed  steel  tie  type  of  track,  is  practically  the  same  as  in  standard 
railroad  construction.  This  type  of  track,  therefore,  is  really  standard  railroad 
track  in  miniature.  The  old  type  of  open  end  corrugated  tie  is  usually  4 inches 
or  4§-  inches  wide  and  32  inches  long,  whereas  the  pressed  steel  tie  is  5^  inches 
wide  and  42^  inches  long.  The  pressed  steel  tie  has  a flange,  approximately  1 
inch  deep,  entirely  around  the  sides  and  ends  of  the  tie.  Not  only  does  this 
flange  grip  the  ground  so  as  to  prevent  shifting  of  the  track,  but  it  prevents 
soil  flow  and  by  its  confining  aotion  increases  the  bearing  power  of  the  soil. 

The  importance  of  this  confining  aotion  is  indicated  by  the  investigations  of  the 
Joint  Committee  on  Track  Stresses,  which  emphasizes  the  importance  of  filling  the 
space  between  ties  with  ballast  up  to  the  top  of  the  tie  so  as  to  prevent  flow  of 
the  ballast.  Not  only  is  the  superficial  bearing  area  of  the  pressed  steel  tie 
traok  considerably  greater  than  that  of  the  corrugated  tie  track,  but  the  confin- 
ing aotion  of  the  flanges  is  such  that  the  carrying  capacity  of  the  pressed  steel 


. 

. •• 

. 


o 


5. 


■ 


tie  track  is  practically  double  that  of  the  narrow,  open  and  corrupted  tie 
track.  The  rails  are  riveted  to  the  ties  in  the  pressed  steel  tie  track 
instead  of  being  bolted,  thus  providing  greater  rigidity  and  consequently 
lessened  danger  of  local  deformations  over  soft  spots  in  the  road  bed. 

The  use  of  a joint  tie  is  another  important  feature  of  the  pressed  steel  tie 
type  of  track,  for  it  provides  a supported  joint  instead  of  the  suspended 
type  common  to  the  corrugated  tie  track.  This  joint  tie  lessens  the 
danger  of  surface  sends,  while  at  the  same  time  it  is  equipped  with  a special 
device  which  eliminates  the  necessity  for  splice  plates  and  bolts.  The 
pressed  steel  tie  track  shown  in  the  photograph  below  has  been  in  use  two 
years  in  Illinois  soil,  and  has  Deen  relaid  perhaps  a half  dozen  times  or 
more. 

In  order  to  insure  ease  of  portability  and  consequent  low  cost  of  laying 
and  removing  light  railway  track,  investigation  and  experience  indicates 
that  the  wneel  loads  to  which  the  track  is  subjected  should  not  exceed  l^r 
tons.  This  limits  the  wei^it  of  four  wheeled  locomotives  to  6 tons,  or  at 
the  most  8 tons.  If  it  is  necessary  to  use  heavier  locomotives,  they  should 
oe  of  the  eigfrt  wheeled  type.  An  eight  wheeled  locomotive  weighing  up  to 
12  tons,  or  at  the  most  16  tons,  can  be  used  on  portable  light  railway  track 
without  harming  the  track.  In  order  to  retain  the  quality  of  portability  in 
light  railway  track  the  rail  should  not  exceed  20  pounds  per  yard  in  weight 
though  sometimes  25  pound  rail  is  used.  The  standard  length  of  section 
equipped  with  6 pressed  steel  ties  riveted  to  the  rail  and  1 joint  tie,  as 
manufactured  by  the  Lakewood  Engineering 
Company,  is  345  pounds.  A mile  of  such 
track,  containing  352  sections,  v/ill 
weigh  60.72  tons.  Experience  has  shown 
that  a 24-inch  g£’.uge  of  track  gives 
sufficient  stability  to  the  rolling  stock, 
which  is  specially  designed  with  a low 
center  of  gravity,  and  does  not  require 
more  room  than  is  generally  available  on 
the  shoulder  of  a road. 

In  laying  light  railway  track  the 
sections  are  placed  on  flat  cars,  and  the 
laying  of  the  track  proceeds  from  the  un- 
loading point  outward,  four  men  are 
generally  required  to  handle  a section  of 
track,  and  8 men  in  charge  of  a foreman 
can  generally  lay  about  one -half  mile  of 
track  under  normal  conditions  in  10  hours. 

At  prevailing  wages  the  cost  of  laying 
ana  removing  a mile  of  lignt  railway 
track  has  been  found  to  oe  about  $200.00, 
exclusive  of  frei^it  and  unloading. 


i 

t 

I 

; 


5 

1 


PRESSED  STEEL-TIE  TYPE  CF  TRACK 


26 


SIX-TON  WHITCOMB  GASOLENE  LOCOMOTIVE 

Very  few  suitable  steam  locomotives  are  in  the  market  at  the  present 
time  as  most  of  them  are  single  truck  and  are  entirely  too  heavy  for  light  port- 
able track.  The  Davenport  Locomotive  Works,  of  Davenport,  Iowa,  manufacture  a 
single-truck,  8-ton  steam  locomotive  which  seems  to  be  well  suited  to  light  rail- 
way operation  in  highway  construction.  The  Lima  Locomotive  Works,  of  Lima,  Ohio, 
manufacture  a double-truck,  10-ton  locomotive  of  the  Shay,- geared  type  especially 
for  road  construction. 


LAYING  LIGHT  RAILWAY  TRACK 

The  type  of  locomotive  commonly  employed  in  light  railway  haulage  on 
highway  construction  at  the  present  time,  is  a four-wheeled  gasolene  machine 
weighing  from  3 to  6 tons.  Inasmuch  as  grades  of  3 and  4 per  cent  are  frequently 
encountered  even  in  level  country,  the  6 ton  locomotive  is  the  type  recommended 
for  general  use.  Detailed  specifications  for  a typical  machine  will  be  found  in 
the  appendix. 


27. 


LIMA  10  TON,  DOUBLE  TRUCK  STEAM  LOCOMOTIVE 


PLYMOUTH  6 TON  GASOLENE  LOCOMOTIVE 

When  light  railways  were  first  extensively  used  in  highway  construction, 
in  1919,  a V shaped  type  of  body  containing  separate  compartments  for  sand,  stone 
and  cement  was  carried  on  a running  gear.  Since  that  time  the  hatch  box  system 
has  been  developed,  enabling  2 boxes  to  be  carried  per  car.  Two  general  types  of 
batch  boxes  are  on  the  market,  namely  the  tip-over  and  the  drop  bottom  type, 
either  of  which  can  be  supplied  with  or  without  separate  compartments  for  sand, 
stone  and  cement.  The  best  practice  favors  the  use  of  cement  compartments,  and 
some  stateB  will  not  permit  cement  to  be  dumped  into  the  same  compartment  with 
sand  and  stone.  The  advantage  of  the  tip-over  type  of  box  lies  in  the  absence  of 
movable  parts  or  fastenings,  while  the  disadvantage  is  the  difficulty  in  tipping 
because  of  the  lowering  of  the  center  of  gravity  & Ls  a smaller  batch  is  used  than 
that  for  which  the  box  was  designed.  This  latter  objection  has  been  overcome, 
however,  by  the  use  of  adjustable  trunnion  plates,  which  enable  the  point  of 
attachment  of  the  lifting  bail  to  be  lowered  as  the  center  of  gravity  of  the  box 
is  lowered.  The  best  type  of  tip-over  batch  boxes  are  of  steel  construction  with 


28 


adjustable  trunnion  plates  and  a separate  cement  compartment  which  can  be  entirely 
removed  or  moved  toward  one  end  or  the  other  in  accordance  with  varying  ratios  of 
sand  and  stone.  The  cement  compartment  should  be  provided  with  a lid,  and  should 
be  raised  from  the  bottom  of  the  batch  box  so  that  rain  penetrating  the  sand  and 
stone  will  not  moisten  the  cement.  Complete  drawings  and  specifications  for  one 
of  the  most  widely  used  types  of  tip-over  batch  boxes  will  be  found  in  the 
appendix. 


BATCH -BOX  SYSTEM  OF  LIGHT  RAILWAY  HAULAGE 


Batch  box  cars  are  generally  arranged  to  carry  two  boxes  per  car,  as 
shown  in  the  preceding  photograph,  when  the  size  of  batch  does  not  exceed  5 bags. 
For  a size  of  batch  suitable  for  a 28-E  paving  mixer,  only  one  box  is  carried 
per  car.  At  the  present  time  the  Easton  Car  & Construction  Company,  of  Easton, 
Penna.  are  manufacturing  a car  for  carrying  three  batch  boxes  of  the  4 bag  type. 
Considerable  difficulty  is  experienced,  however,  in  swinging  the  middle  batch 
box  in  and  out  of  place.  Considerable  thought  has  been  given  to  the  manufacture 
of  a double  truck  platform  car  for  carrying  4 or  more  batches.  To  date,  however, 
such  a car  has  been  found  to  cost  more  per  batch  than  a single  truck  car,  while 
the  difficulty  of  handling  the  middle  batch  boxes  is  such  as  to  discourage  its 
use.  A double  truck  car  is  easier  on  the  track  than  the  single  truck  type, and 
undoubtedly  the  double  truck  car,  equipped  perhaps  with  automatic  couplers,  will 
come  into  general  use  later  on.  A common  type  of  double  truck  car  used  for 
general  utility  hauling  is  illustrated  in  the  photograph  on  the  following  page. 

When  light  railway  haulage  was  first  applied  to  highway  construction 
the  train  speed  was  very  low, due  to  the  poor  character  of  track  used,  and  did  not 
exceed  3 or  4 miles  per  hour.  Under  such  conditions  cars  equipped  with  mild  steel 
axles  designed  with  an  ordinary  factor  of  safety,  were  found  to  be  satisfactory 
and  very  little  axle  trouble  occurred.  With  the  introduction  of  the  pressed  steel 
tie  type  of  track  properly  laid  and  maintained  and  with  proper  limits  placed  upon 
the  weight  of  locomotives,  operating  speeds  increased  to  as  high  as  20  and  25 
miles  per  hour  in  some  cases  with  an  average  of  8 to  10  miles.  Under  these  con- 
ditions considerable  trouble  was  encountered  thru  the  breakage  of  mild  steel 
axles,  which,  investigations  by  metallurgists,  showed,was  due  to  so-called  fatigue 
of  metal  induced  by  rapid  reversal  of  stress.  It  was  found  necessary,  therefore. 


29. 


to  increase  the  factor  of  safety  considerably,  and  to  employ  heat-treated,  high  - 
carbon  steel  axles.  This  is  the  type  of  construction  used  in  the  best  cars  at  the 
present  time. 

When  light  railway  haulage  was  first  applied  to  highway  construction, 
cars  equipped  with  brass  or  bronze  bearings  were  considered  plenty  good  enough. 

The  heavy  locomotives  used  at  that  time  possessed  a hauling  capacity  more  than 
sufficient  to  compensate  for  the  increased  rolling  resistance  resulting  from  the 
use  of  bearings  of  this  type.  With  the  advent  of  the  modern  improved  type  of 
track,  permitting  higher  speeds,  and  recognition  of  the  fact  that  wheel  loads  of 
locomotives  should  not  exceed  1-g-  tons,  the  weight  of  locomotive  was  decreased  to 
such  an  extent  that  it  became  necessary  to  reduce  the  rolling  resistance  of  cars 
to  a minimam.  The  caged-roller  type  of  bearing,  and  in  many  oases  high  class 
bearings  such  as  the  Hyatt  roller  bearing  were,  therefore,  adopted,  and  all  the 
best  cars  at  the  present  time  are  equipped  with  such  bearings.  Actual  tests  in 
the  field  by  dynamometer  have  shown  that  whereas  the  rolling  resistance  of  cars 
equipped  with  brass  or  bronze  bearings  varj^from  30  up  to  70  pounds  per  ton,  the 
rolling  resistance  of  cars  equipped  with  caged  roller  bearings  operating  on  a 
high  carbon,  heat-treated  axle  has  not  exceeded  10  pounds  per  ton.  Spring  draw 
bars  and  bumpers  and  spring  pedestals  characterize  the  modern  light  railway  car, 
as  oompared  to  the  old  type.  The  appendix  oontains  specifications  of  one  of  the 
most  widely  used  types  of  batch  box  cars  on  the  market  today. 


DOUBLE 'TRUCK,  GENERAL-UTILITY  PLATFORM  CAR 

The  indifferent  success  attending  light  railway  haulage  in  highway 
construction  previous  to  1919,  was  largely  due  to  failure  to  operate  the  railway 
on  standard  railroad  principles.  Very  little  attempt  was  made  to  deliver  material 
at  any  predetermined  rate  to  the  concrete  mixer,  or  to  operate  trains  on  a 
schedule.  The  result  was  an  erratic  and  undependable  supply  of  material,  and  the 
operation  of  trains  in  a '’hit-or-miss*',  haphazard  fashion.  To  operate  trains  on 
a light  railway  on  a definite  schedule  was  generally  considered  impossible  or 
impractical,  and  with  the  frequent  derailments  caused  by  the  make-shift  character 
of  equipment  perhaps  it  was  really  so.  Light  railway  operation  under  the  severest 
conditions  in  military  operations,  however,  has  indicated  the  entire  feasibility 
of  running  light  railway  equipment  of  proper  design  on  definite  schedule  in 


30 


accordance  with  standard  railroad  principles. 

The  modern  conception  of  light  railway  operation  applied  to  highway 
construction  is  that  a light  railway  is  merely  a commercial  railway  in  miniature 
under  intensive  traffio,  and  that  all  problems  peculiar  to  standard  railroad 
practice  apply  with  equal  force  to  the  operation  of  a light  railway.  The  use  of 
field  telephones  similar  to  those  employed  in  military  service  in  order  to  control 
the  movement  of  trains,  has  even  been  contemplated  on  light  railway  operations 
applied  to  highway  construction  of  large  extent.  Modern  practice  demands  the  use 
of  equipment  of  the  highest  type,  especially  designed  for  the  conditions  peculiar 
to  highway  construction.  Proper  recognition  of  these  fundamental  factors  has 
resulted  in  the  large  success  which  has  attended  the  use  of  light  railway  haulage 
in  highway  construction  during  the  past  two  years. 


/ 


* 


4 


31. 


CHAPTER  V. 


TYPES  OF  LIGHT  RAILWAY  PLANTS. 


Two  types  of  light  railway  plant  are  commonly  used  in  highway  construc- 
tion, the  complete  railway  plant  and  the  combined  railway  and  motor  truck:  plant. 

As  its  name  indicates  the  complete  railway  plant  affords  complete  transportation 
facilities  for  a job,  while  the  combined  railway  and  motor  truck  plant  makes  use 
of  light  railway  in  combination  with  motor  trucks.  The  combined  light  railway 
and  motor  truck  plant  has  been  developed  to  overcome  certain  limitations  to  the 
use  of  the  complete  railway  plant  on  some  jobs.  These  limitations  are  topographic, 
geographic,  size  of  job,  financial  ability  of  the  contractor,  and  necessity  for 
utilizing  truck  equipment  on  hand. 

The  topographic  limitations  are  due,  not  so  much  to  the  steepness  of 
any  one  grade,  as  to  the  distribution  of  grades.  If  only  one  steep  grade  is  en- 
countered it  can  generally  be  negotiated  by  means  of  the  split  train  method,  the 
booster  locomotive  method,  the  hoisting  engine  method,  or  the  balanced  train 
method,  as  described  in  the  following  chapter.  If,  however,  a large  number  of 
quite  widely  separated  steep  grades  occur,  it  becomes  necessary  to  use  a booster 
locomotive  or  one  of  the  other  methods  at  each  grade.  This  would  make  the  cost 
of  a plant  exceedingly  high.  By  using  only  a mile  and  a half  of  track,  in  a 
manner  described  later  on,  the  chances  are  that  not  more  than  one  steep  grade 
would  be  included  in  the  railway  portion  of  the  haul.  The  investment  in  auxiliary 
grade  olimbing  equipment  would  thus  be  reduced  very  considerably.  Another  topo- 
graphic limitation  to  the  use  of  a complete  railway  system  on  some  jobs  in  hilly 
country,  is  due  to  the  fact  that  the  road  frequently  lies  on  a ridge,  along  which 
the  grades  are  such  as  to  make  railway  haul  feasible.  The  unloading  point,  how- 
ever, might  be  located  in  a valley,  and  the  grade  on  a road  leading  from  the  un- 
loading point  might  be  excessively  steep.  In  such  a case  the  best  method  of  op- 
eration would  be  to  haul  material  in  motor  trucks  from  the  unloading  point  to 
the  road  under  construction,  where  it  could  be  transferred  to  light  railway  oars 
for  haul  to  the  mixer. 

The  geographic  limitation  to  the  use  of  complete  railway  haulage  on 
some  jobs  arises  from  the  fact  that  the  unloading  point  is  sometimes  located  with- 
in the  corporate  limits  of  a city  or  town.  It  is  generally  impractical  to  lay 
light  railway  track  on  the  streets  leading  from  the  unloading  point  to  the  road 
under  construction.  In  such  a case  material  is  hauled  in  motor  trucks  from  the 
unloading  point  to  the  job,  where  it  is  transferred  to  light  railway  cars  for 
haul  to  the  mixer. 

The  purchase  of  a complete  light  railway  road  building  plant  naturally 
entails  a considerable  investment.  In  order  to  justify  this  investment  and  insure 
an  adequate  return  on  it,  it  is  necessary  that  the  job  be  of  a certain  minimum 
size.  Of  course  if  the  contractor  has  a number  of  short  jobs  located  quite  close- 
ly together  he  has  what  practically  amounts  to  one  big  job,  and  in  such  a case 
a complete  railway  plant  can  be  economically  justified  on  a smaller  job  than  if 
only  one  were  available.  This  question  will  be  considered  in  detail  in  a later 
chapter,  but  suffice  it  here  to  say  that  on  those  jobs  too  small  to  justify  a 
complete  railway  plant,  a combination  of  light  railway  and  motor  trucks  can  be 
used.  This  combination  gives  the  contractor  practically  all  of  the  benefits  of 
railway  haulage,  while  at  the  same  time  it  reduces  his  investment  to  a minimum. 


3 2. 


Quite  frequently  a contractor  is  unable  to  make  the  proper  financial 
arrangements  for  the  purchase  of  a complete  railway  plant,  even  though  he  recog- 
nizes the  economy  and  desirability  of  such  a plant  on  a certain  job.  He  might  be 
in  a position,  however,  to  purchase  about  a mile  and  a half  of  track  and  a com- 
mensurate amount  of  rolling  stock  to  use  in  conjunction  with  motor  trucks,  and  thus 
secure  the  advantages  of  railvsay  haulage. 

Sometimes  a contractor  possesses  a considerable  amount  of  motor  truck 
equipment  and  desires  to  make  use  of  it,  while  at  the  same  time  he  realizes  the 
economy  of  railway  haulage  and  desires  to  take  advantage  of  it.  In  such  a case 
a combined  plant,  using  about  a mile  and  a half  of  track,  will  permit  the  contrac- 
tor to  use  his  motor  trucks  and  at  the  same  time  secure  the  advantages  of  railway 
haulage.  Later  on, if  desired,  he  can  easily  add  to  his  railway  equipment,  so  as 
to  secure  a complete  railway  plant. 

In  certain  sections  of  the  country  the  average  road  job  will  be  5 or  6 
miles  long,  or,  if  longer,  the  unloading  points  will  be  so  located  as  to  permit  a 
10  or  12  mile  job  to  be  handled  by  means  of  a few  miles  of  track.  Occasionally 
a 10  or  12  mile  job  will  occur  on  which  all  the  material  must  be  hauled  from  one 
end.  This  would  necessitate  the  use  of  10  or  12  miles  of  track  with  a proportion- 
ate amount  of  rolling  stock,  in  order  to  operate  with  a complete  railway  system. 

A contractor  would  probably  find  the  purchase  of  so  much  equipment  uneconomical 
for  only  one  job,  inasmuch  as  he  would  have  but  very  little  use  for  more  than  about 
one-third  of  it  on  the  majority  of  his  work.  In  such  a case  a few  rented  motor 
trucks  used  in  conjunction  with  the  railway  equipment  he  already  possesses,  will 
enable  him  to  secure  the  benefits  of  railway  haul  without  a large  additional  in- 
vestment in  equipment. 

The  combined  light  railway  and  motor  truck  plan  of  operation  has  been 
developed  in  order  to  meet  the  limitations  to  the  use  of  a complete  railway  plant 
on  some  jobs  as  set  forth  in  the  preceding  paragraphs.  In  the  combined  light 
railway  and  motor  truck  plan  of  operation,  batch  boxes,  each  containing  complete 
materials  for  one  batch,  are  carried  on  motor  trucks  from  the  material  yard  to  the 
road  under  construction  and  over  the  finished  pavement  as  far  as  specifications 
permit. 


BATCH  BOXES  CARRIED  ON  MOTOR  TRUCKS 


33 


Practioally  all  state  specifications  permit  traffic  over  the  finished 
concrete  road  after  the  expiration  of  21  days,  and  over  the  finished  concrete 
base  after  the  expiration  of  from  10  to  14  days.  At  the  point  where  the  concrete 
is  not  sufficiently  cured  to  carry  traffic,  the  loaded  batoh  boxes  are  transferred 
from  the  trucks  to  light  railway  cars  for  haul  pasiedr  the  uncured  portion  of  the 
concrete  to  the  mixer.  It  is  obvious  that  this  plan  of  operation  requires  only 
sufficient  railway  track  to  extend  past  the  portion  of  the  concrete  not  yet  suffi- 
ciently cured  to  carry  traffic.  Each  day  as  a section  of  concrete  comes  of  proper 
age  to  carry  traffic  the  transfer  point  oan  be  advanced,  and  the  track  no  longer 
needed  in  the  rear  can  be  picked  up  and  relaid  in  advance  of  the  mixer.  A small 
crane  or  a light  portable  derrick  with  an  18  foot  boom  and  about  2 ton  capacity, 
is  the  best  device  for  transferring  batoh  boxes  from  truck  to  railway  cars  and 
vice  versa.  An  "A"  frame  spanning  the  road  equipped  with  a chain  hoist  and  a 
trolley  is  sometimes  used  as  a transfer  device. 


HAULING  MATERIAL  OVER  CURED  CONCRETE,  COMBINED  SYSTEM 


TRANSFERRING  BATCH  BOXES  FROM  TRUCK  TO  CARS 


34 


The  combined  light  railway  and  motor  truck  plant  possesses  practically 
all  the  advantages  of  a oomplete  railway  plant,  such  as  elimination  of  wheeling 
and  shoveling  crew,  reduction  of  labor  in  trimming  and  retrinming  subgrade, 
elimination  of  lost  and  dirty  material  due  to  dumping  on  the  subgrade,  etc*  Inas- 
much as  the  motor  trucks  operate  over  an  improved  road  and  the  remainder  of  the 
haul  is  over  steel  rails,  delay  due  to  rainy  weather  should  be  reduced  to  a mini- 
mum. The  combined  light  railway  and  motor  truck  plan  of  operation,  in  common 
with  the  complete  railway  plan,  permits  the  placing  of  conorete  to  begin  at  the 
point  nearest  the  material  yard.  This  eliminates  delay  in  placing  concrete, and 
permits  the  concreting  and  grading  operations  to  be  performed  simultaneously,  A 
large  monthly  estimate  is  thus  insured  early  in  the  life  of  the  job,  and  much 
needed  working  capital  provided. 

The  railway  portion  of  a oombined  light  railway  and  motor  truck  haulage 
system,  can  easily  be  extended  at  any  time  so  as  to  form  a complete  railway  plant. 
Where  a contractor  desires  to  reduce  his  investment  to  a minimum  it  is  recommended 
that  motor  trucks  be  rented,as  a trucking  company  can  afford  to  rent  their  trucks 
for  less  than  the  cost  to  a contractor  of  operating  his  own  truoks.  This  is  due 
to  the  fact  that  the  trucking  company  operates  all  the  year  round,  while  the  con- 
tractor operates  only  a part  of  the  year  and  must  absorb  all  the  plant  charges 
during  the  short  road  building  season*  While  not  quite  so  economical  as  a com- 
plete railway  plant,  where  conditions  permit  this  type  to  be  used,  the  oombined 
light  railway  and  motor  truck  plant  will  effect  very  considerable  economy  over 
other  methods  of  doing  work  where  material  is  dumped  on  the  subgrade  or  all  of  the 
haulage  is  performed  over  it.  The  combined  light  railway  and  motor  truck  plant 
offers  to  the  contractor  of  limited  means  an  opportunity  to  perform  his  work  in  an 
economical  manner,  and  as  he  secures  more  capital  he  can  add  to  his  equipment,  if 
desired,  so  as  to  eventually  secure  a complete  railway  plant.  In  operating  a oom- 
bined plant,  practically  all  contractors  rent  the  motor  truoks. 

Sometimes  material  is  hauled  in  dump  body  trucks  and  is  dumped  near  a 
small  portable  bin,  into  which  it  is  handled  by  a crane  equipped  with  a clam  shell 
bucket  , a bucket  elevator,  a portable  bucket  loader,  or  a short  belt  conveyor. 
Material  is  occasionally  dumped  on  the  finished  pavement  at  the  transfer  point  and 
shoveled  into  the  batch  boxes  on  the  cars  by  hand,  when,  for  some  reason,  a con- 
tractor does  not  desire  to  install  a portable  derrick  or  bin.  This  method  is  not 
economical  and  is  only  a make-shift.  To  supply  a 14-E  paving  mixer  a gang  of  from 
8 to  10  shovelers  are  needed.  The  objection  to  the  method  of  hauling  material  in 
bulk  is  the  expensive  rehandling  equipment  necessitated,  and  the  cost  of  this 
rehandling.  The  best  method  of  operating  a combined  plant  is  to  load  the  batch 
boxes  with  complete  materials  at  the  material  yard,  haul  them  out  to  the  road  on 
motor  trucks,  and  transfer  to  railway  oars  by  means  of  a portable  derrick.  When 
batch  box  haulage  is  used  it  is  unnecessary  to  haul  cement  bags  out  on  the  road 
and  thus  risk  losing  them,  or  bulk  cement  can  be  employed.  The  method  of  lauling 
material  in  bulk  precludes  the  economy  in  handling  cement  which  the  batch  box  sys- 
tem insures.  Another  advantage  of  the  batch  box  plan  is  the  fact  that  a platform 
truck  or  a plain  truck  chassis  equipped  with  a light  wooden  frame  to  hold  the  batch 
boxes, can  be  used.  This  reduces  the  cost  of  rental  or  purchase  of  trucks  andin- 
creases  the  number  available  for  service.  Dump  body  trucks  can  also  be  used  to 
oarry  batoh  boxes  if  necessary.  Many  times  it  is  practical  to  use  trailers  with 
the  batch  box  system,  and  inasmuoh  as  these  trailers  are  double  ended  the  problem 
of  turning  them  is  solved. 

The  oomplete  railway  plant,  as  previously  mentioned,  affords  oomplete 
transportation  facilities  for  a job.  Detailed  plans  of  operation  for  this  type  of 
plant, will  be  considered  in  a later  chapter. 


25 


A problem  quite  frequently  encountered  in  operating  a light  railway 
plant,  is  that  of  crossing  the  tracks  of  a standard  gauge  railway.  Wherever  it  is 
possible  to  avoid  crossing  standard  gauge  tracks  they  should  be  avoided,  but  if 
necessary  the  crossing  can  be  readily  effected.  Some  railroads  require  a contrac- 
tor to  post  watchmen  about  a half  mile  on  each  side  of  the  crossing  point* equipped 
with  telephones,  in  order  to  notify  the  crossing  watchman  of  the  approach  of 
trains.  Other  railroads  do  not  require  these  precautions,  and  are  content  if  a 
watchman  is  placed  at  the  crossing  itself.  Needless  to  say  the  contractor  should 
take  every  precaution  to  insure  against  an  accident  at  the  crossing  point. 

A number  of  different  methods  have  been  devised  for  carrying  light 
railway  track  over  standard  gauge  track.  All  these  methods  are  alike  in  that  no 
outting  of  the  rails  in  the  standard  gauge  track  is  contemplated,  nor  would  it  be 
permitted  by  the  railroad  oompany.  The  type  of  crossing  consists  of  a section 
of  light  railway  track  placed  over  the  standard  gauge  track,  in  such  a fashion 
that  the  light  railway  track  can  be  removed  after  each  passage  of  the  train.  The 
photographs  below  illustrate  a number  of  light  railway  crossings. 


LIGHT  RAILWAY  GROSSING  HINGED  HORIZONTALLY 


36 


COUNTERBALANCED  LIGHT  RAILWAY  CROSSING  HINGED  VERTICALLY 


The  first  of  the  foregoing  illustrations  shows  a 15  foot  section  of 
light  railway  traok  hinged  at  one  oorner  so  as  to  permit  it  to  he  swung  horizon- 
tally away  from  the  standard  gauge  track  after  the  passage  of  each  train.  The 

I second  illustration  shows  two  Yg-  foot  sections  of  track  hinged  so  as  to  he  swung 
hack  vertically  away  from  the  standard  gauge  track.  The  third  illustration  shows 
two  7-§-  foot  sections  hinged  vertically,  and  so  equipped  as  to  he  swung  hack  vertL 
oally  hy  means  of  counterweights.  These  counterweights  are  attached  to  lines 
passing  over  sheaves  on  the  "A”  frame.  The  particular  crossing  illustrated  in 
this  photograph  was  at  a point  where  the  standard  gauge  railroad  was  located  on  a 
steep  grade,  and  on  a curve  in  a cut  of  considerable  depth. 


37. 


CHAPTER  VI. 


GRADES,  SPEED  AND  SIZE  OF  TRAINS 


The  hauling  capacity  of  a locomotive  is  a function  of  the  weight  on  the 
driving  wheels,  and  the  character  of  metal  in  the  wheel.  With  equal  weight  on  the 
drivers  and  the  same  type  of  metal  in  the  wheels,  the  hauling  capacity  of  one  type 
of  locomotive  is  the  same  as  that  of  another  if  sufficient  engine  power  is  provi- 
ded to  slip  the  driving  wheels  on  dry  rail.  In  full  sized  commercial  locomotives 
some  allowance  must  he  made  for  the  effeot  of  the  reciprocating  parts  on  rod 
driven  locomotives  as  compared  to  gear  driven  or  electric  driven  machines,  hut 
for  the  small  locomotives  used  on  light  railway  the  foregoing  statement  is  true. 


Tractive  effort  is  the  force  exerted  hy  the  locomotive  at  the  drivers, 
and  is  a function  of  the  adhesion  between  the  driving  wheels  and  the  rails.  All 
of  this  force,  however,  is  not  available  for  pulling  a train,  as  a certain  amount 
of  it  is  consumed  in  overcoming  the  rolling  resistance  of  the  locomotive  itself. 

The  force  at  the  draw  bar  of  the  locomotive  available  for  pulling  a train,  is 
equal  to  the  tractive  effort  minus  the  rolling  resistance  of  the  locomotive  itself. 
The  engine  power  provided  is,  of  course,  partly  consumed  in  overcoming  friction 
within  the  mechanism  of  the  locomotive,  and  in  other  losses. 


The  factor  of  adhesion  between  steel  rails  and  steel  driving  wheels  is 
generally  taken  at  25  per  cent  when  the  rail  is  dry,  while  the  factor  of  adhesion 
between  cast  iron  wheels  with  a chilled  tread  and  a dry  rail  is  generally  taken 
at  20  per  cent.  When  the  rail  is  wet  both  of  these  factors  are  reduced  consider- 
ably, but, on  the  other  hand,  the  application  of  sand  will  serve  to  increase  them 
up  to  a limit  of  approximately  40  and  35  per  cent  for  steel  and  oast  iron  wheels 
respectively. 

The  rolling  resistance  of  a train  is  the  force  required  to  maintain  a 
constant  speed  by  overcoming  the  retarding  influence  of  friction  in  the  bearings, 
friction  between  wheels  and  rails,  and  all  other  forces  tending  to  retard  the  move- 
ment of  the  train.  The  force  required  to  accelerate  a train  must  not  only  over- 
come the  rolling  resistance, but  it  must  also  overcome  the  inertia.  The  force 
employed  in  overcoming  the  inertia  of  a train  is  stored  in  the  train  in  the  form 
of  kinetio  energy,  which  later  on  tends  to  keep  the  train  in  motion  when  the  speed 
is  reduced.  It  is  apparent,  therefore,  that  greater  force  is  required  to  acceler- 
ate a train  than  to  keep  it  going  after  a start  has  once  been  made.  The  retarding 
influences  of  friction  would  in  time  consume  the  kinetic  energy  stored  in  a train, 
providing,  it  was  operating  on  the  level  so  that  the  force  of  gravity  would  not 
come  into  play,  but  brakes  are  provided  in  order  to  consume  this  kinetic  energy 
thru  the  medium  of  friction  to  enable  the  train  to  be  stopped  wherever  desired. 

In  standard  railroad  praotioe  where  trains  operate  at  a high  rate  of  speed,  the 
effect  of  atmospheric  resistance  must  be  taken  into  account.  This  factor  can  be 
neglected,  however,  in  the  small  trains  operated  at  the  comparatively  low  rate  of 
speed  prevailing  on  light  railway  employed  in  highway  construction. 


The  frictional  resistance  of  bearings  forms  the  greater  part  of  the 
rolling  resistance  of  a train,  and  this  frictional  resistance  depends  largely  upon 
the  type  of  bearing  used.  In  standard  railroad  practioe  the  rolling  resistance 
of  cars  in  good  condition  is  generally  about  5 or  6 pounds  per  ton,  but  the  rolling 
resistance  of  light  railway  cars  varies  from  10  to  70  pounds  per  ton.  The  lower 
value  is  obtained  when  caged  roller  bearings  and  high  carbon,  heat-treated  axles 


38 


are  used,  while  values  from  20  pounds  up  to  70  pounds  prevail  with  "brass  or  "bronze 
hearings  and  mild  steel  axles.  The  importance  of  reducing  rolling  resistance  to 
a minimum  is  apparent  when  we  consider  that  a locomotive  can  pull  practically 
three  times  as  heavy  a train  on  the  level  with  a rolling  resistance  of  10  pounds 
per  ton  as  it  can  pull  with  rolling  resistance  at  30  pounds  per  ton.  The  limited 
draw  "bar  pull  available  in  the  small  type  of  locomotive  featured  in  modern  light 
railway  practice  in  order  that  wheel  loads  will  not  exceed  lg-  tons,  makes  reduc- 
tion of  rolling  resistance  of  cars  to  a minimum  doubly  important. 


The  effect  of  grades  is  to  increase  the  rolling  resistance  of  a train 
20  pounds  per  ton  for  each  per  cent  of  grade,  and  to  decrease  the  draw  bar  pull  of 
the  locomotive  20  pounds  per  ton  weight  of  the  locomotive.  This  is  due  to  the 
effect  of  gravity,  and  a proof  of  this  phenomena  can  easily  be  effected  by  means 
of  a diagram  of  forces.  The  application  of  this  law  can  perhaps  best  be  demon- 
stated  by  means  of  an  example. 

A 6 ton  locomotive  having  a weight  of  12,000  pounds  on  its  drivers  and 
cast  iron  driving  wheels  with  chilled  treads,  will  have  a draw  bar  pull  of  2,400 
pounds  on  the  level.  Such  a locomotive  is  capable  of  pulling  a train  weighing 
120  tons  on  the  level,  with  a rolling  resistance  of  20  pounds  per  ton.  Inasmuch 
as  the  draw  bar  pull  of  the  locomot  ive  is  decreased  20  pounds  for  each  ton  of 
weight  for  each  per  cent  of  grade, the  draw  bar  pull  on  a 1 per  cent  grade  would  be 
2,280  pounds*  The  rolling  resistance  of  a train,  on  the  other  hand,  is  increased 
20  pounds  per  ton  for  each  per  cent  of  grade,  making  the  rolling  resistance  40 
pounds  per  ton  on  a 1 per  cent  grade.  The  locomotive  we  have  in  mind,  therefore, 
could  pull  a train  weighing  57  tons  on  a 1 per  cent  grade.  It  is  thus  apparent 
that  a 1 per  cent  grade  will  reduce  the  hauling  capacity  of  a locomotive  to  less 
than  half  of  its  capacity  on  the  level,  when  the  rolling  resistance  of  the  train 
on  the  level  is  20  pounds  per  ton.  If  the  rolling  resistance  on  the  level  is  only 
10  pounds  per  ton,  the  hauling  capacity  of  a locomotive  would  be  reduoed  by  one- 
half  on  a grade  of  only  one-half  of  one  per  cent.  The  serious  effect  of  grades 
on  the  size  of  a train  is  thus  clearly  apparent,  and  shows  why  standard  railroad 
practice  generally  sets  a maximum  of  about  three-tenths  of  one  per  cent  to  its 
main  line  grade.  The  lower  the  rolling  resistance  of  the  cars,  the  greater  is  the 
influence  exerted  by  grades  on  the  size  of  train. 

The  hauling  capacity  of  any  locomotive  can  easily  be  computed  in  the 
manner  shown  above,  but  sometimes  a formula  showing  the  relations  between  the 
speed  and  hauling  capacity  is  convenient.  For  sake  of  illustration  a formula 
of  this  kind, applicable  to  a typical  6 ton  gasolene  locomotive  widely  employed 
in  light  railway  haulage  in  highway  const ruction, will  be  derived.  This  locomo- 
tive is  equipped  with  a 50  horse  power  engine  and  can  exert  a draw  bar  pull  on  the 
level  of  2,400  pounds  at  5 miles  per  hour  and  1200  pounds  at  10  miles  per  hour. 

The  adhesion  of  the  driving  wheels  to  the  rail  is  20percent  under  normal  condi- 
tion. The  rolling  resistance  of  the  train  will  be  assumed  to  be  20  pounds  per  ton. 


Let 

Let 

Let 

Let 

Let 

Let 

Let 

Let 

Let 

Let 


E 

W 

S 

L 

G 

V 

H* 

H 

E 

D 


repre  sent 

t» 


train  resistance  on  the  level 
weight  of  train  in  tons 
speed  in  miles  per  hour 
distance  traveled  in  feet  per  minute 
per  cent  of  grade 

vertical  distance  lifted  in  feet  per  minute 
engine  horse  power 
draw  bar  horse  power 

ratio  of  draw  bar  horse  power  to  engine  horse  power 
draw  bar  pull  in  pounds 


39 


L = 526°.  s.  = 88  S 

60 

D L - e H»  - D 86  S - D S 

33000  ” ~ 33000  375 

H = E H’ 

When  S = 10,  D = 1200,  therefore  E = 0.64  and  H - 0.64  H* 
H*  z 50,  therefore  H I 32 
R I 20  W V : G L : 88  G S 


H - R L f 2000  (¥  + 6)  V = 20  W 88  S 4 2000  (W  4 6)  88  S 5 z 
33000  33000 


S £~W  » 100  G (W  4 6l?  - 


s = 


18.76 

600 


32 


+ 100  G (W  + 6) 


nr  _ 600  (1  - G S]  n _ 600  - W 3 

* w “ S (1  * 100  &)*  5 “ 100  S (w  + 6) 


Experience  has  shown  that  the  performance  of  locomotives  in  the  field  is 
entirely  in  accordance  with  the  expressions  for  S,  W,  and  G shown  above.  In 
applying  this  formula,  however,  in  which  the  hauling  capacity  of  the  looomotive 
varies  inversely  with  the  speed,  it  must  not  be  forgotten  that  the  limiting  faotor 
at  all  times  is  the  adhesion  between  the  driving  wheels  and  the  rails.  For 
instance. if  we  assume  a grade  of  4 |)er  cent  and  a speed  of  2 miles  per  hour,  we 
get  a value  for  W of  55.2  tons.  Inasmuch  as  the  rolling  resistance  of  the  train 
is  increased  20  pounds  per  ton  for  each  per  cent  of  grade,  the  draw  bar  pull  nec- 
essary to  haul  a train  of  this  weight  up  a 4 per  cent  grade  is  5,520  pounds.  We 
have  previously  seen,  however,  that  the  maximum  draw  bar  pull  which  a 6 ton  locomo- 
tive equipped  with  cast  iron  drivers  can  exert  is  20  per  cent  of  its  weight, or 
2,400  pounds.  It  is  apparent,  therefore,  that  a locomotive  of  this  type  cannot 
haul  a 55  ton  train  up  a 4 per  cent  grade.  The  discrepancy  arises  from  the  fact 
that  the  formula  does  not  apply  for  speeds  lower  than  5 miles  per  hour,  because  at 
lower  speeds  the  pull  which  the  engine  of  the  locomotive  can  develop  exceeds  the 
adhesion  of  the  locomotive  to  the  rail.  In  other  words  the  draw  bar  pull  will  not 
be  increased  tjy  operation  at  a speed  lower  than  5 miles  per  hour,  as  the  formula 
indicates,  on  account  of  the  limiting  factor  of  the  adhesion  of  the  driving  wheels 
to  the  rail.  It  is  entirely  possible  to  operate  the  locomotive  at  speeds  much 
lower  than  5 miles  per  hour,  but  the  draw  bar  pull  will  not  vary  inversely  with 
the  speed, as  indicated  by  the  formula,  when  the  rate  is  less  than  5 miles  per  hour. 
Of  course  if  the  rails  are  sanded  or  steel  driving  wheels  are  used  on  the  locomo- 
tive, the  adhesion  will  be  increased  to  such  an  extent  that  the  draw  bar  pull  will 
vary  inversely  with  the  speed, as  shown  by  the  formula,  at  rates  lower  than  5 miles 
per  hour.  It  is  not  wise,  however,  to  assume  conditions  other  than  those  of 
normal  dry  rail.  The  limiting  factor  to  the  hauling  power  of  any  looomotive  is 
the  adhesion  between  the  driving  wheels  and  the  rail,  and  engine  power  in  excess  of 
that  required  to  spin  the  driving  wheels  under  normal  conditions  will  not  increase 
the  hauling  power. 


40 


A 3 ton  gasolene  locomotive,  equipped  with  cast  iron  driving  wheels, of  the 
type  conmonly  used  in  highway  construction,  can  exert  a draw  bar  pull  on  the  level 
of  1,200  pounds  at  5 miles  per  hour  and  600  pounds  at  10  miles  per  hour  under 
normal  conditions.  The  formula  for  the  hauling  capacity  of  this  locomotive  is 

W - 300  (1  - G S) 

“ S (1  + 100  G)* 

If  steel  driving  wheels  are  used,  in  place  of  cast  iron  wheels  with 
chilled  tread,  the  factor  of  adhesion  between  the  drivers  and  the  rails  will  be 
increased  to  25  per  cent.  A 6 ton  looomotive  with  steel  drivers  can  exert  a draw 
bar  pull  on  the  level  of  3,000  pounds  at  5 miles  per  hour,  and  1,500  pounds  at  10 
miles  per  hour.  The  formula  for  hauling  capacity  for  a 6-ton  locomotive  with 

steel  drivers  will  be  ¥ = 7£P  ~ s4-«  W z 87,5  (1  - fi  S)  is  the  expression  of 

S (1  f 100  G)  S (1  + 100  G) 

hauling  capacity  of  a 3 ton  looomotive  equipped  with  steel  drivers.  The  principal 
advantage  of  steel  driving  wheels  is  not  the  increased  draw  bar  pull  on  the  level 
resulting  therefrom,  but  the  increased  hauling  capacity  on  grades. 

The  effect  of  gravity  is  to  retard  a train  ascending  a grade,  and  to 
reduce  the  hauling  power  of  the  locomotive.  On  descending  grades,  however,  gravity 
tends  to  increase  the  speed  of  the  train,  and  to  decrease  the  draw  bar  pull  re- 
quired to  overcome  the  rolling  resistance  of  the  train.  When  the  grade  is  suffi- 
ciently steep  the  draw  bar  pull  required  to  overcome  the  rolling  resistance  of  the 
train  beoomes  negative,  so  that  brakes  must  be  provided  to  retard  the  train.  The 
effect  of  gravity  on  a descending  grade  is  to  exert  a pull  of  20  pounds  per  ton 
weight  of  train  and  locomotive  for  each  per  cent  of  grade.  On  a 1 per  cent  des- 
cending grade,  therefore,  the  effect  of  gravity  is  just  sufficient  to  overcome  the 
rolling  resistance  of  a train  of  20  pounds  per  ton.  On  descending  grades  a high 
rolling  resistance  is  an  advantage,  for  it  assists  in  retarding  the  train  and 
thus  makes  oontrol  by  means  of  brakes  easier. 

In  standard  railroad  practice,  grades  known  as  velocity  grades  are  fre- 
quently used.  These  grades  consist  of  opposing  descending  and  ascending  grades. 

On  the  descending  grade  the  train  is  permitted  to  run  without  the  application  of 
brakes,  and  the  kinetic  energy  attained  is  utilized  to  ascend  the  opposing  grade. 

In  this  manner  the  force  of  gravity  is  called  into  play  so  as  to  reduce  fuel  con- 
sumption. In  light  railway  operation  as  applied  to  highway  construction,  however, 
velocity  grades  are  generally  not  practical,  because  of  the  light  equipment  and 
the  temporary  character  of  the  track. 

The  effect  of  a descending  grade  on  the  speed  of  a train  can  be  demon- 
strated in  the  following  manner: 


Let 

V represent 

the  velocity  in  feet  per  second 

Let 

KE 

n 

the  kinetio  energy  of  a train  at 

V feet  per  second 

Let 

S 

it 

speed  in  miles  per  hour 

Let 

g 

it 

the  acceleration  of  gravity 

Let 

H 

•» 

height  in  feet  to  which  KE  will 

lift  train 

Let 

W 

n 

weight  of  locomotive  and  train  in  pounds 

Let 

G 

tt 

per  cent  of  grade 

Let 

L 

M 

horizontal  distance  in  feet 

Let 

E 

It 

rolling  resistance  at  20  pounds 

per  ton  : ^ 

41 


H , V = 1.467  S,  H = 0.03344  S2,  S = 5.47^H“ 

2 g 

H - G L, 


V2  : 2 g H : 2 g 5 L 


KE  z l/2  M V2  ; l/2  — 2 gG  L If  SL  : the  kinetic  energy  of  the  train 

2 A ® 

providing- the  rolling  resistance  were  zero.  The  retarding  action  due  to  rolling 

V/  L 

resistance,  however,  is  "^oo* 


¥5  1-  ” l/2  MV2:  w ^ = actual  KE  of  train. 

100  2 g 


51- 


100  “ 2 g * 


«2  _ 100  G L - L 
1,55  ’ 


100  G L - L Z 1.55  V' 

- t/L  .UQQ-Gl^-11 
1.55 


V6  z 2.15  S' 


s2  L (100  G - 1)  g _ ,/L  (100  G - 1), 

1 3.31  ’ 3.31 

S represents  speed  due  to  the  effect  of  gravity,  assuming  the  train 
starts  from  the  top  at  a stand  still.  If  the  train  approaches  the  top  of  the  grade 
at  a certain  speed,  this  speed  should  he  added  to  that  due  to  gravity  in  order  to 
obtain  the  final  speed  at  the  bottom  of  the  grade. 

A train  with  a rolling  resistance  of  20  pounds  per  ton, will  attain  a 
speed  due  to  gravity  of  25  miles  per  hour  at  the  bottom  of  500  feet  of  5 per  cent 
grade.  If  the  train  resistance  is  less  than  20  pounds  per  ton,  the  speed  attained 
would  be  even  greater  than  25  miles  per  hour.  While  speeds  of  20  and  25  miles  per 
hour  are  occasionally  attained  on  light  railway  used  in  highway  construction,  it 
is  not  considered  wise  to  operate  at  a rate  of  speed  exceeding  10  or  15  miles  per 
hour. 

The  braking  power  of  a locomotive  depends  upon  the  adhesion  of  the  driv- 
ing wheels  to  the  rail,  in  the  same  manner  that  the  hauling  power  depends  upon 
this  factor.  Theoretically,  therefore,  a locomotive  can  control  the  same  weight 
of  train  on  a descending  grade, by  means  of  its  brakes,  that  it  can  haul  up  an 
ascending  grade.  An  overloaded  locomotive  on  an  ascending  grade  will  stop  of  its 
own  accord,  however,  while  an  overloaded  locomotive  on  a descending  grade,  if  the 
cars  are  net  equipped  with  brakes,  cannot  be  stopped.  Descending  grades  are  a 
greater  source  of  danger  and  must  be  more  carefully  watched, than  ascending  grades. 
Fortunately  it  is  unnecessary  to  depend  upon  the  brakes  on  the  locomotive  alone, 
for  brakes  can  also  be  placed  on  the  cars.  On  a light  railway  train,  however, 
automatic  brakes  are  too  expensive,  and  it  is  not  practical  to  apply  brakes  on  more 
than  three  cars,  one  next  to  the  locomotive  and  two  at  the  end  of  the  train,  unless 
additional  men  are  provided  for  this  purpose.  As  a rule  but  one  train  man  is 
provided,  and  he  ride3  between  the  two  last  cars  in  order  to  apply  the  brakes  on 
them.  The  brakes  on  the  car  next  to  the  locomotive  can  be  applied  by  the  locomo- 
tive operator.  The  braking  power  of  cars  is  oomputed  in  the  same  manner  as  that  of 
the  locomotive,  by  multiplying  the  weight  of  the  car  by  the  factor  of  adhesion  be- 
tween the  wheels  and  the  rails. 


* 


42 


As  mentioned  in  the  foregoing  paragraph  speeds  of  20  and  25  miles  per 
hour  are  sometimes  attained  in  light  railway  operation,  hut  the  average  operating 
speed  is  from  8 to  10  miles  per  hour.  Experience  indicates,  however,  that  an  aver- 
age speed  of  6 miles  per  hour  is  the  proper  speed  to  use  in  proportioning  the 
amount  of  rolling  stock  required.  In  rolling  country  where  the  ascending  and 
descending  grades  balance  one  another  fairly  well  in  length  and  degree.,  the  speed 
of  operation  is  almost  as  great  as  it  is  in  level  country.  This  is  due  to  the 
fact  that  descending  grades  compensate,  to  a certain  extent,  for  the  ascending 
grades.  Due  to  the  necessity  of  applying  brakes  in  order  to  keep  the  speed  within 
safe  limite,  the  descending  grades  do  not  entirely  compensate  for  the  ascending 
grades.  In  most  cases,  however,  an  average  speed  of  6 miles  per  hour  can  be  used 
as  a basis  for  proportioning  the  amount  of  rolling  stock  required  in  hilly  country 
as  well  as  in  level  country. 

If  desired, the  average  speed  of  operation  in  hilly  country  can  be  com- 
puted from  a profile  by  means  of  the  formula  derived  on  page  39.  This  formula  en- 
ables the  speed  of  train  to  be  computed  on  grades,  while  on  level  sections  the 
speed  can  be  assumed  at  10  miles  per  hour.  On  down  grades, also, a speed  of  10  miles 
per  hour  can  be  used.  On  an  ascending  grade  the  speed  derived  from  the  formula 
will  be  the  speed  at  the  top  of  the  grade,  and  the  mean  speed  for  the  entire  grade 
can  be  obtained  by  averaging  the  speed  at  the  top  and  the  speed  at  which  the  train 
approached  the  bottom.  The  mean  speed  of  a down  grade  can  be  obtained  by  averaging 
the  speed  at  which  the  train  approached  the  top,  and  the  assumed  speed  of  10  miles 
per  hour  at  the  bottom.  While  this  is  not  strictly  correct, it  is  accurate  enough 
for  all  practical  purposes.  The  average  operating  speed  for  the  entire  job  can 
then  be  obtained  by  multiplying  the  length  of  each  grade  and  level  stretch  by  its 
average  speed,and  dividing  the  sum  of  these  products  by  the  total  length  of  the 
road.  Exoept  where  ascending  or  descending  grades  predominate,  it  is  seldom  nec- 
essary to  go  to  the  refinement  of  computii^g  the  weighted  mean  speed  from  the  pro- 
file. 

Specifications  generally  require  concrete  to  be  mixed  a certain  minimum 
time,  generally  one  minute.  Under  such  conditions  a 14-E  paving  mixer  should  aver- 
age about  30  batches  per  hour,  and  a 21 -E  paving  mixer  about  the  same.  A 28-E 
paving  mixer  should  produce  about  24  batches  per  hour.  The  object  of  light  railway 
haulage,  therefore,  is  not  to  deliver  the  maximum  amount  of  material  possible  be- 
tween two  points,  but  rather  to  so  coordinate  haulage  operations  as  to  supply  the 
mixer  at  a predetermined  rate  of  about  30  batches  per  hour.  The  size  of  train 
should  be  such  as  to  supply  the  mixer  at  the  predetermined  rate  during  the  interval 
between  arrival  of  trains,  providing  topographic  conditions  are  such  as  to  permit 
this  to  be  done.  In  level  country  it  is  possible  to  haul  trains  of  30  to  40 
loaded  cars,  but  unless  the  length  of  haul  is  such  that  the  intervals  between  the 
arrival  of  trains  at  the  mixer  are  sufficiently  great  to  enable  the  mixer  to  con- 
sume the  amount  of  material  carried  by  such  a train,a  train  of  this  size  would  not 
be  economical.  In  other  words  the  size  of  trains  on  any  particular  job  is  not 
always  determined  by  topographic  conditions, and  consequently  the  hauling  capacity 
of  the  looomotive,  but  often  by  the  length  of  time  required  per  round  trip  between 
mixer  and  material  yard.  The  time  element  as  well  as  the  topographic  element  must 
be  considered  in  determining  the  size  of  trains. 

Suppose, for  instance, that  operations  were  being  carried  on  in  level 
country  on  a 2 mile  haul,  and  that  a 6 ton  locomotive  could  haul  a 40  car  train. 

At  a speed  of  6 miles  per  hour,  the  locomotive  would  make  a round  trip  in  40  minutes. 
Allowing  5 minutes  for  switching  trains  at  the  mixer  and  the  same  amount  of  time 
at  the  material  yard,  a total  of  50  minutes  would  be  required  per  round  trip.  Three  ! 
trains  would  be  necessary,  1 at  the  mixer,  1 at  the  material  yard,  and  1 in  transit 4 


4 


v 


43 


A 40  oar  train  would  carry  80  batches,  or  a sufficient  amount  of  material  to  supply 
the  mixer  for  160  minutes  at  the  rate  of  30  batches  per  hour.  On  the  round  trip 
of  4 miles  the  locomotive  can  arrive  at  the  mixer  at  50  minute  intervals,  and 
during  this  interval  the  mixer  would  consume  only  about  25  batches.  A train  of  12 
or  13  cars,  therefore,  would  be  sufficiently  large  to  supply  the  mixer  at  the 
predetermined  rate.  If  40  oar  trains  were  used  a total  of  120  cars  and  240  batch 
boxes  would  be  needed,  while  3 trains  of  13  cars  each  would  make  a total  of  only 
39  cars  and  78  batch  boxes.  It  is  obvious,  therefore,  that  in  this  case  it  would 
not  be  economical  to  load  the  locomotive  up  to  its  maximum  hauling  capacity.  The 
point  it  is  desired  to  emphasize  is  that  in  level  oountry  the  size  of  train  is 
frequently  determined  by  the  length  of  running  time  between  the  mixer  and  the 
material  yard,  because  the  rate  of  operation  of  the  mixer  is  limited  by  specifica- 
tions. The  problem  of  operating  a light  railway  in  highway  construction  is  not 
merely  one  of  transporting  a maximum  amount  of  material  between  two  points,  but 
rather  one  of  so  coordinating  the  transportation  efforts  as  to  supply  the  mixer 
with  the  maximum  amount  of  material  which  specifications  permit  it  to  consume. 


TWENTY-FIVE  CAR  TRAIN  IN  ARIZONA 


THREE  CAR  TRAIN  ON  8.2  PER  CENT  GRADE  IN  PENNSYLVANIA 


44 


1 


The  preceding  photographs  illustrate  very  clearly  the  effect  of  grades 
on  the  size  of  trains.  The  locomotives  employed  in  "both  of  these  operations  are 
6 ton  gasolene,  friction  drive  machines,  of  equal  hauling  oapacity. 

In  level  country  the  length  of  running  time  "between  the  mixer  and  the 
material  yard  frequently  determines  the  size  of  train,  but  in  hilly  country,  of 
oourse,  the  size  of  train  is  limited  by  the  grades.  It  is  necessary,  therefore, 
to  run  trains  at  more  frequent  intervals  in  hilly  country  than  in  level  country. 
The  influence  which  grades  exert  upon  light  railway  haulage,  however,  is  not  so 
much  due  to  the  actual  steepness  of  the  grade,  as  it  is  to  their  number  and  dis- 
tribution. If  only  one  steep  grade  exists  on  a job  it  oan  be  surmounted  by  means 
of  a booster  locomotive,  or  one  of  the  other  methods  described  in  the  following 
paragraphs.  If  the  steep  grades  are  many  in  number, or  so  distributed  that  a 
booster  locomotive  or  some  other  method  is  required  at  each  grade,  the  question  of 
grades  becomes  serious  because  of  the  increased  amount  of  equipment  required. 

Several  methods  of  negotiating  steep  grades  are  in  general  use  at  the 
present  time.  The  principal  methods  are  known  as  the  booster  method,  the  split 
train  method,  the  hoisting  engine  method,  and  the  balanced  train  method. 

The  booster  method  consists  of  using  an  extra  locomotive  to  push  or 
pull  a train  up  a steep  grade.  By  this  method  a train  of  approximately  twice  the 
weight  that  a single  locomotive  can  handle,  can  be  taken  up  a grade.  Instead  of 
using  an  extra  locomotive, other  motive  power  such  as  a motor  truck,  a tractor, 
or  even  a team  of  horses  is  sometimes  used  to  pull  a train  up  a grade.  Auxiliary 
motive  power  of  this  kind  is  generally  used  where  but  one  steep  grade  must  be 
considered. 


BOOSTER  LOCOMOTIVE  METHOD  OF  NEGOTIATING  STEEP  GRADES 

Perhaps  the  most  popular  method  of  surmounting  steep  grades,  is  by  what 
is  known  as  the  split  train  method.  In  this  method  the  looomotive  is  placed  in  the 
middle,  and  half  of  the  train  taken  up  the  grade  at  a time.  The  split  train  me- 
thod is  especially  adapted  to  a job  containing  but  one  steep  grade,  and  in  such  a 
case  it  is  generally  more  economical  than  the  booster  locomotive  method.  A certain 
amount  of  time  is  lost,  of  course,  by  the  split  train  method,  and  where  a number 
of  grades  exist  the  running  time  is  sometimes  so  increased  that  it  is  questionable 


45 


whether  to  purchase  the  additional  cars  and  locomotive  needed  to  properly  supply 
the  mixer  or  to  purchase  booster  locomotives.  Conditions  surrounding  each  job 
must  govern  in  such  a case. 


MOTOR  TRUCKS  HAULING-  TRAIN  UP  STEEP  GRADE 


The  time  required  to  negotiate  a grade  by  the  split  train  method  can  be 
estimated  in  the  following  manner:  Assume  a 6 per  cent  grade  1,000  feet  long. 

Under  normal  conditions,  a 6 ton  locomotive  equipped  with  steel  driving  wheels  will 
pull  a 5 car  train  carrying  10  batches  up  such  a grade.  Assume  that  the  other 
grades  are  such  that  an  8 car  train  can  be  used.  By  placing  the  locomotive  in  the 
center  of  the  train,  4 cars  can  be  taken  up  the  6 per  cent  grade  at  a time.  The 
weight  of  a 4 oar  train,  each  car  carrying  2-4  bag  batches  of  material,  is  about 
13-l/2  tons,  and  a 6 ton  looomotive  will  haul  such  a train  up  a 6 per  cent  grade 
at  a speed  of  5*5  miles  per  hour  or  484  feet  per  minute.  Assuming  the  train  stops 
100  feet  from  the  bottom  of  the  grade  and  runs  the  same  distance  beyond  the  top, 
the  locomotive  should  cover  the  distance  of  1,200  feet  in  about  2.5  minutes. 

Coming  down  the  grade  the  locomotive  will  average  about  10  miles  per  hour,  so  that 
1.5  minutes  are  needed  for  this  purpose.  Allowing  l/2  minute  at  the  bottom  of  the 
grade  to  set  brakes  on  oars  and  to  uncouple  and  the  same  amount  of  time  at  the  top 
of  the  grade,  a total  of  2 minutes  will  be  required  for  this  purpose.  Adding  the 
time  required  to  run  up  and  down  the  grade,  gives  a total  of  8.5  minutes  which  are 
required  to  negotiate  this  grade  by  the  split  train  method.  At  a speed  of  6 miles 
per  hour,  a train  will  travel  1 mile  in  10  minutes.  The  extra  time  consumed  on 
this  grade  due  to  splitting  the  train  is  6 minutes,  so  that  the  effect  of  this 
grade  is  the  same  as  if  the  haul  were  increased  0.6  of  a mile.  If  a number  of 
grades  are  encountered,  it  is  obvious  that  the  running  time  of  trains  might  be  so 
increased  as  to  necessitate  additional  equipment  in  order  to  properly  supply  the 
mixer. 

The  hoisting  method  of  steep  grade  operation,  consists  of  placing  a 
hoisting  engine  at  the  top  of  the  grade  and  attaching  a line  to  the  train.  The 
pull  which  can  be  obtained  from  the  hoisting  engine  depends  upon  the  si£e  of  the 
engine,  and  upon  the  size  and  speed  of  the  drum.  When  a hoisting  engine  is  used 
to  assist  a train  up  a steep  grade,  it  should  be  set  at  one  side  of  the  road  and 
the  cable  passed  around  a sheave  in  the  center  of  the  track.  Empty  trains  on  the  i 


46 


way  down  grade,  pull  the  cable  to  the  bottom  in  order  that  it  may  be  in  readiness 
for  the  next  ascending  train.  The  hoisting  engine  method  is  limited  by  the  line 
capacity  of  the  drum,  and  by  curves  in  the  traofc. 

The  balanced  train  method  utilises  the  weight  of  the  empty  descending 
train  to  assist  the  loaded  train  up  the  grade,  by  means  of  a cable  passed  around 
sheaves  at  the  top.  Double  traofc  is  generally  used  in  this  method,  but  a single 
traofc  with  a passing  siding  half  way  up  can  be  used  if  the  sheaves  at  the  top  are 
both  placed  outside  of  the  rails.  In  operation  the  cable  is  attached  to  the  rear 
car  of  the  empty  train  at  the  top  of  the  grade,  and  to  the  loaded  train  at  the 
bottom  of  the  grade.  The  operator  on  the  empty  train  allows  his  train  to  descend 
without  the  application  of  brakes,  so  as  to  give  the  force  of  gravity  full  play. 

In  this  method  of  operat ion, the  loaded  and  empty  trains  alternately  occupy  right 
anA  left  hand  tracks  or  passing  siding.  Assume  a 6 ton  locomotive  with  steel 
wheels  is  to  negotiate  a 6 per  cent  grade,  with  an  8 car  train.  Such  a train, 
each  car  carrying  2-4  bag  batohes  of  material,  would  weigh  about  27.2  tons.  On 
a 6 per  cent  grade  the  locomotive  could  exert  a draw  bar  pull  of  2,280  pounds* 
while  a train  of  this  weight,  with  a rolling  resistance  of  20  pounds  per  ton  on 
the  level,  would  require  a pull  of  3,808  pounds.  An  additional  pull  of  1,528 
pounds  over  the  draw  bar  pull  must  be  provided, if  the  train  is  to  be  hauled  up  the 
grade  in  question.  An  empty  car  carrying  2 steel  batch  boxes  will  weigh  2,000 
pounds,  so  that  the  empty  train  with  the  locomotive  will  weigh  14  tons.  The 
influence  of  gravity  will  cause  a pull  of  20  pounds  per  ton  for  each  per  cent  of 
grade,  or  120  pounds  per  ton  on  a 6 per  cent  grade.  Subtracting  the  rolling  re- 
sistance of  20  pounds  per  ton,  leaves  a net  pull  of  100  pounds  due  to  gravity. 

The  pull  delivered  by  the  14  ton  descending  train,  therefore,  would  equal  1,400 
pounds.  Inasmuch  as  an  additional  pull  of  1,528  pounds  is  required,  the  weight 
of  the  descending  train  is  hardly  sufficient.  By  the  use  of  sand,  however,  this 
grade  could  be  surmounted  very  nicely.  If  the  rolling  resistance  were  only  10 
pounds  per  ton  the  descending  train  would  furnish  a 1,540  pound  pull,  while  the 
additional  pull  needed  by  the  ascending  train  would  be  only  1,256  pounds. 

Sometimes  it  is  possible  to  so  arrange  passing  sidings  and  schedules, 
that  trains  will  meet  either  at  the  top  or  the  bottom  of  the  grade.  In  such  a 
case  the  looomotive  on  the  empty  train  can  be  detaohed,  and  utilized  as  a booster. 
The  delay  would  not  be  quite  as  great  as  that  required  by  the  split  train  method, 
but  the  location  of  the  passing  siding  at  the  top  or  bottom  of  the  trade  might 
oause  a serious  derangement  of  the  operating  sohedule.  At  times,  however,  this 
method  can  be  employed,  and  it  is  well  to  keep  it  in  mind. 

Considerable  thought  and  study  has  been  given  to  the  problem  of  develop- 
ing a raofc  and  pinion  method  for  use  on  steep  grades.  The  idea  is  to  bolt  the 
rack  to  the  track  in  sections,  and  to  place  a pinion  on  an  axle  of  the  locomotive 
so  that  it  would  mesh  with  the  rack  in  somewhat  the  same  manner  as  in  the  cog 
wheel  system.  The  difficulty  of  securing  proper  meshing  between  the  rack  and 
pinion  is  such,  that  to  date  this  method  has  not  proven  practical. 

Whenever  possible  it  is  preferable  to  pull  a train  by  means  of  the 
locomotive,  rat  her  than  to  push  it.  Pushing  a train  causes  the  car  wheels  to  jam 
against  the  rail,  and  not  only  increases  the  rolling  resistance  but  increases  the 
possibility  of  derailment.  The  increased  rolling  resistance  caused  by  pushing 
light  railway  trains,  is  such  as  to  reduce  the  capacity  of  the  locomotive  very  con- 
siderably. 

The  6 ton  gasolene  locomotive  is  the  type  best  adapted  to  light  railway 


47 


operation  in  highway  construction  at  the  present  time,  inasmuch  as  the  wheel  loads 
to  not  exceed  l-l/2  tons  and  the  draw  "bar  pull  is  sufficient  to  enable  a fair  size 
train  to  he  used.  In  level  country  the  3 or  4 ton  looomotive  is  frequently  used, 
hut  even  here  opinion  is  gaining  ground  that  the  6 ton  machine  is  the  best  type. 

A 10  ton  geared  looomotive  on  double  truoks  suitable  for  highway  construction, 
illustrated  on  page  27,  is  manufactured  by  the  Lima  Locomotive  Works,  of  Lima,  Ohio 
The  difficulty  of  designing  a small  machine  of  this  type,  so  the  manufacturers 
claim,  is  suoh  that  the  available  draw  bar  pull  is  not  commensurate  with  the  weight 
of  the  machine.  The  draw  bar  pull  on  this  locomotive  is  only  3,400  pounds,  in- 
stead of  the  5,000  pounds  which  a machine  of  this  weight,  equipped  with  steel 
wheels,  should  deliver.  This  particular  locomotive  does  not  possess  sufficient 
engine  power  to  develop  the  draw  bar  pull  which  its  weight  would  enable  it  to 
deliver,  and  obviously  it  is  not  as  efficient  a unit  as  a 6 ton  locomotive  which 
utilizes  all  of  its  weight  in  pulling  a train.  The  additional  weight  in  an  under- 
powered looomotive  is  of  advantage  only  for  braking  purposes. 

There  is  urgent  need  at  the  present  time  for  a 10  or  12  ton  double 
truck  gasolene  locomotive,  designed  with  a low  center  of  gravity  and  a short  wheel 
base.  No  such  machine  is  on  the  market,  in  fact  there  are  really  no  satisfactory 
locomotives  exceeding  6 tons  in  weight  available  for  light  railway  operation  in 
highway  construction  today.  Experience  indicates  that  gasolene  is  the  best  fuel 
for  light  railway  operation  in  highway  construction. 

Three  ton  machines,  as  a rule,  are  not  used  on  grades  exceeding  4 per  cent, 
while  6 ton  locomotives  are  in  successful  operation  in  the  State  of  Pennsylvania 
on  grades  up  to  8 per  cent.  The  photograph  on  page  43  shows  a 6 ton  locomotive 
hauling  a 3 oar  train  up  an  8.2  per  cent  grade,  each  car  carrying  2-4  bag 
batches  of  material  for  a 1-2-3  concrete.  The  question  of  limiting  grades  is  not 
one  of  the  maximum  grade  which  a locomotive  can  climb,  but  one  which  it  can  climb 
while  pulling  a train  of  at  least  3 cars.  Theoretically  a locomotive  can  climb  a 
20  per  cent  grade  on  dry  rail,  but  this  is  of  no  practical  interest  to  the  con- 
tractor for  he  is  concerned  only  in  the  size  of  train  which  a locomotive  can 
handle  on  a given  grade.  Very  seldom  are  grades  in  excess  of  10  per  cent  permitted 
on  any  road  which  is  to  be  improved  with  a so-called  permanent  pavement,  and  if 
steeper  grades  do  occur  they  are  generally  short  and  can  be  handled  by  one  of  the 
methods  previously  described.  Experience  during  the  past  two  years  indicates  that 
light  railway  haulage  can  be  economically  employed,  on  any  grades  which  are  likely 
to  be  encountered  on  roads  inportant  enough  to  be  inproved  with  a pavement  involv- 
ing the  use  of  concrete. 


48 


CHAPTER  VII. 


TRAIN  SCHEDULES  AND  LOCATIONS  OF  SIDINGS. 


It  has  previously  "been  pointed  out  that  one  of  the  reasons  for  the 
indifferent  success  which  attended  the  early  efforts  to  apply  light  railway  haul- 
age to  highway  construction,  was  the  lack  of  proper  train  schedules  and  failure 
to  operate  trains  in  a systematic  manner.  In  order  properly  to  operate  a light 
railway  system  so  as  to  supply  material  to  the  mixer  at  the  required  rate,  it  is 
necessary  that  the  trains  he  operated  on  regular  schedule.  Each  train  should  he 
given  a number,  and  the  operator  inqpressed  with  the  fact  that  he  is  to  leave  the 
material  yard  at  such  and  such  a time,  to  meet  other  trains  at  passing  sidings  at 
such  and  such  a time,  and  to  arrive  at  and  leave  the  mixer  at  a certain  time.  A 
time  schedule  should  he  computed,  and  should  he  changed  from  time  to  time  as  the 
length  of  the  haul  necessitates.  In  order  to  assist  in  maintaining  the  schedule 
and  to  insure  that  help  is  speedily  forthcoming  in  case  of  trouble,  field  tele- 
phones similar  to  those  employed  by  the  United  States  Army  can  he  used.  These 
phones  are  not  very  expensive,  and  they  can  he  attached,  in  many  cases,  to  wire 
fences  along  the  way.  On  a big  job  these  telephones  could  he  used  to  control  the 
movement  of  trains.  While  such  an  arrangement  might  seem  elaborate  at  the  present 
time,  refinements  of  this  character  will  come  into  more  general  use  as  the  value 
of,  and  necessity  for,  good  organization  is  more  fully  realized. 

Schedules  can  he  computed  and  used  in  either  tabular  or  graphical  form. 
The  computation  of  a tabular  schedule,  from  which  a graphical  schedule  can  he 
constructed,  is  shown  below.  The  length  of  haul  from  the  material  yard  to  the 
mixer  is  assumed  to  he  4 miles,  and  the  speed  of  the  train  6 miles  per  hour.  An 
allowance  of  5 minutes  for  lost  time  on  switches  is  made,  though  the  rate  of  oper- 
ation, 6 miles  per  hour,  is  generally  sufficiently  low  to  provide  for  this  feature. 
An  allowance  of  5 minutes  for  switching  trains  at  the  mixer  and  the  same  amount 
of  time  at  the  material  yard,  is  made.  An  8-  car,  16-hatch  train,  is  assumed,  with 
the  mixer  operating  at  30  hatches  per  hour. 


Train 

Arrive 

Leave 

Arrive 

Leave 

Arrive 

number 

at  yard 

Yard 

at  miser 

Mixer 

at  yard 

1 

7:10 

7:15 

8:00 

8:05 

8:50 

2 

7:42 

7:47 

8:32 

8:37 

9:22 

3 

8:14 

8:19 

9:04 

9:09 

9:54 

1 

8:46 

8:51 

9:36 

9:41 

10:26 

The  schedule  shows  that  train  #1  arrives  at  the  yard  at  8:50,  practi- 
cally in  time  to  take  the  place  of  what  would  have  been  train  #4.  Consequently 
on  this  particular  job,  3 locomotives  would  be  sufficient.  Inasmuch  as  one  train 
is  left  at  the  mixer  while  another  is  at  the  material  yard  and  still  another  is 
attached  to  each  locomotive,  it  is  apparent  that  5 trains  of  8 cars  each  are  re- 
quired or  a total  of  40  oars  and  80  hatch  boxes.  Not  only  does  this  schedule  in- 
dicate the  time  at  which  trains  are  to  leave  and  arrive  at  various  points,  hut  it 
also  indicates  the  amount  of  rolling  stock  required. 

A short-out  method  of  determining  the  amount  of  rolling  stock  required 
consists  of  computing  the  round-trip  time,  and  consequently  the  number  of  round 
trips  per  day.  For  instance,  in  the  foregoing  example  a 4-mile  haul  is  assumed  at 


_i 


49 


6 miles  per  hour,  with  a 5-minute  delay  on  switches,  at  the  mixer,  and  at  the 
material  yard.  The  time  required  per  round  trip  is  100  minutes,  enabling  a loco- 
motive to  make  6 round  trips  per  10-hour  day.  Each  car  carries  2 hatches,  so  that 
6 train  loads  of  8 cars  each  amount  to  96  batches.  Three  locomotives,  therefore, 
could  deliver  approximately  300  batches  to  the  mixer,  and  by  speeding  up  a trifle 
they  could  easily  deliver  300  batches.  The  determination  of  the  number  of  trains 
and  cars  required,  is  effected  as  in  the  previous  method. 

A time  schedule,  similar  to  the  one  shown  on  the  preceding  page,  should 
be  tabulated  for  the  entire  day.  As  the  length  of  haul  increases  and  the  loca- 
tion of  the  sidings  are  changed,  the  time  schedule  should  be  properly  modified. 

In  order  to  maintain  train  schedules  it  is  necessary  that  passing  sid- 
ings be  located  at  the  correct  places,  for  if  this  is  not  done  considerable  time 
will  be  lost  by  trains  waiting  for  each  other.  In  the  past  improper  attention  has 
been  paid  to  this  feature  of  light  railway  operation,  or  if  the  sidings  were 
correotly  located  at  first  they  were  not  changed  as  the  length  of  haul  and  the 
number  of  trains  changed.  The  difficulty  of  changing  siding  locations  with  the 
make-shift  type  of  track  employed  in  the  past,  was  no  doubt  responsible  to  a large 
degree  for  neglect  of  this  important  feature.  The  track  in  use  at  the  present 
time  is  manufactured  especially  for  light  railway  operation  in  highway  construc- 
tion, and  is  so  designed  as  to  permit  of  easy  and  rapid  changing  of  passing  sid- 
ings. 

As  the  length  of  haul  from  the  material  yard  to  the  mixer  varies,  it  is 
necessary  also  to  vary  the  number  of  trains  in  order  to  properly  and  economically 
supply  the  mixer.  The  locations  of  passing  sidings  must  accordingly  be  changed 
from  time  to  time.  It  is  generally  cheaper  to  Change  the  location  of  a siding 
a quarter  of  a mile,  than  it  is  to  allow  the  delay  caused  by  the  improper  location 
to  increase  the  running  time  of  trains  so  that  the  required  number  of  batches  can 
not  be  delivered  to  the  mixer.  Of  course, it  is  frequently  impractical  to  locate 
sidings  exaotly  where  the  train  schedules  require  them  to  be  because  of  narrow 
shoulders,  but  this  can  often  be  easily  and  cheaply  corrected  by  means  of  a small 
amount  of  cribbing.  In  any  event  an  attempt  should  be  made  to  approximate  the 
correct  location  as  closely  as  possible.  As  a rule  no  movement  of  a siding  of 
much  less  than  a quarter  of  a mile  is  necessary  or  justified. 

Steep  grades  are  sometimes  surmounted  by  placing  passing  sidings  at  the 
top  or  bottom,  and  uncoupling  the  locomotive  from  the  empty  train  to  assist  the 
loaded  train  up  a grade.  This  practice  will  occasionally  avoid  the  purchase  of 
additional  motive  power  and  in  such  a case  might  be  justified,  even  though  the 
location  is  not  the  correct  one  according  to  the  schedule.  If  locating  sidings 
at  the  top  or  bottom  of  a grade  should  so  derange  the  train  schedule  as  to  reduce 
the  output  of  the  mixer,  the  question  of  whether  it  is  less  expensive  to  permit 
this  or  to  purchase  a booster  locomotive  oan  only  be  decided  after  proper  consi- 
deration of  all  factors  peculiar  to  the  job* 

Perhaps  the  best  method  of  determining  the  location  of  passing  sidings 
is  the  graphical  method, shown  in  the  accompanying  graphs.  The  data  on  these 
prints  apply  to  a two  mixer  plant  supplied  from  one  material  yard,  operating  on 
what  is  known  as  a balanced  haul.  The  time  of  leaving  the  material  yard,  arriving 
at  the  mixer,  etc*  is  determined  from  a schedule  such  as  that  shown  on  page  48. 

The  length  of  haul  varies  from  2 miles  to  6 miles,  and  the  locations  of  passing 
sidings  are  determined  by  the  intersection  of  time  ourves  for  the  various  trains. 

Graph  #1,  which  applies  when  both  mixers  are  at  the  4 mile  point,  indi- 


L 


50 


cates  that  returning  train  #1,  serving  mixer  #1,  encounters  outgoing  train  #2, 
serving  mixer  #1,  at  a point  about  2-5/8  miles  from  the  material  yard.  Theoret- 
ically train  #1,  serving  mixer  #1,  encounters  train  #1,  serving  mixer  #2,  at  a 
point  about  3-3/8  miles  from  the  material  yard,  but  inasmuch  as  the  trains  serving 
eaoh  mixer  branch  off  at  the  2 mile  point  this  meeting  in  reality  never  occurs. 
Further  on  we  see  that  train  #1,  serving  mixer  #1,  encounters  train  #2,  serving 
mixer  #2,  train  #3,  serving  mixer  #1,  and  train  #3,  serving  mixer  #2,  at  points 
approximately  1-3/4  miles,  1 mile,  and  l/4  mile  from  the  material  yard  respectively 
At  each  of  these  points  a passing  siding  is  required,  though  the  l/4  mile  siding 
is  so  close  to  the  material  yard  that  the  siding  at  the  material  yard  will  probably 
suffice.  Proceeding  in  a similar  manner  we  find  that  with  mixer  #1  at  the  6 mile 
point  and  mixer  #2  at  the  2 mile  point,  and  with  mixer  #1  at  the  5 mile  point  and 
mixer  #2  at  the  3 mile  point,  that  additional  sidings,  or  sidings  at  different 
locations, are  required. 

When  two  mixers  are  supplied  from  one  material  yard  located  some  dis- 
tance from  the  road  under  construction,  the  small  changes  in  siding  location  re- 
quired on  the  "dead  haul"  road  need  not  generally  be  made.  As  a rule  if  the  sid- 
ings along  the  "dead  haul"  road  are  located  at  the  proper  points  for  serving  the 
mixers  at  the  points  of  average  haul,  these  locations  are  sufficiently  correct 
for  the  other  hauls  involved.  The  sidings  along  the  road  tinder  construction,  how- 
ever, should  be  changed  from  time  to  time,  as  occasion  demands.  As  a rule  sidings 
must  be  placed  approximately  a mile  apart  on  a light  railway  line  serving  one 
mixer,  with  a passing  siding  at  the  mixer  itself.  When  two  mixers  are  supplied 
by  one  line  of  track,  as  on  a road  leading  from  the  material  yard  to  the  road 
under  construction,  approximately  twioe  as  many  sidings  are  needed  as  when  but 
one  mixer  is  used. 

The  application  of  the  method  of  locating  sidings  described  in  the  fore- 
going in  case  only  one  mixer  is  to  be  supplied  from  the  material  yard,  is  a simple 
matter.  A preliminary  study  should  be  made  to  determine  the  proper  location  of 
sidings  for  the  entire  job,  with  the  haul  varying  by  1 mile  intervals  from  the 
minimum  to  the  maximum.  As  the  haul  from  the  material  yard  to  the  mixer  changes, 
sidings  can  be  shifted  accordingly  to  the  points  previously  determined. 

Practical  common  sense  must  always  be  used  in  applying  this  method  of 
siding  looation,  for  it  is  apparent  that  a change  in  the  size  of  trains  or  the 
speed  of  operation  will  necessitate  corresponding  changes  in  the  location  of  sid- 
ings. A study  of  the  passing  siding  problan  in  the  manner  indicated  in  the  fore- 
going, however,  should  do  much  to  eliminate  haphazard  operation  of  trains  and  to 
insure  the  maintenance  of  proper  schedules. 


■- 


y 


I 


f 

\ 


- 


A7/'xcr  ^2. 


/V/‘xcr  S/d/'/r^ 


M/'xcr  

y-"  v.:::.— ;a^., 

*S  rf/dc  r S/W/ntj 


/*7oAer/*/ 

'Yard. 


h S/c/Z/i^s  &/ 


5/D//V&  jLOC/f  7“/  or/ 

for 

3 OTA/  /+7/X.FXS  A ?T  Fo//VT  OF  F/EFFGE  FFUJL. 


IHHH 


77m  or  Zeav/na  &no7  F 7^0  7*7* 7/er/a/  y#ro/. 

*S*€  ScAea'c/ /e  /v'ft  / 


&<e/7£>s>j  ss-z  / 


'rc 


xcr  S/d/ay 


tfsxer  S/X/rn. 


M 


S/gf/aa  &/ 


Wafer/#/  faro'. 


3/D//V&  £ 0C/1 7V  0SV 

far 

/*7/XJE/Z  #/  XT’  S W/^3  /V//^7*  ^*7*f  /y7/X£j?  *Z  *7”  3 /*7/JL3  ^a//YT 


UM 


7~/‘/?7c  af  /.eav/aj  *7/7 o'  fc/r/7  fo  A7a  fe/^/a/  fas'*/. 

+fee  •J’c/fe  a/a/c  A^*- 3 


<5* /=?£>*  /V-g-  3 


51 


CHAPTER  VIII. 


PLAN  OF  OPERATION 


It  is  extremely  difficult,  if  not  impossible,  to  outline  a general 
plan  of  operation  in  highway  construction,  because  local  conditions  vary  so 
greatly  . Some  of  the  more  conmon  conditions  encountered  and  plans  of  operation 
employed  will  be  described,  however,  in  order  to  illustrate  the  application  of  a 
road  building  plant  to  changing  conditions.  The  application  of  both  a complete 
railway  plant  and  a combined  light  railway  and  motor  truck  plant,  will  be  consi- 
dered. 

Under  the  subject  of  a complete  railway  plant,  we  will  consider  the 
following  cases: 

One  mixer  plant,  unloading  point  at  one  end. 

One  mixer  plant,  unloading  point  near  middle. 

One  mixer  plant,  stone  at  one  end  and  sand  at  the  other. 

Two  mixer  plant,  unloading  point  at  one  end. 

Two  mixer  plant,  unloading  point  near  middle. 

Two  mixer  plant,  unloading  points  at  each  end. 

A job  suitable  for  a one  mixer  plant  with  the  unloading  point  at  or 
near  one  end,  is  one  which  is  frequently  seen  in  practice.  The  best  plan  of 
operation  on  such  a job  is  to  start  grading  at  the  end  of  the  road  nearest  the 
material  yard,  and  to  continue  grading  operations  straight  thru  to  the  other  end. 

As  soon  as  a few  hundred  feet  of  subgrade  are  ready,  mixing  operations  can  be 
started  and  carried  on  continuously  to  the  other  end.  The  fact  that  the  laying  of 
concrete  can  be  begun  at  the  point  of  minimum  haul,  is  one  of  the  big  advantages 
of  light  railway  haulage.  Not  only  is  delay  due  to  waiting  on  the  completion  of 
grading  eliminated,  but  concrete  and  grading  operations  can  be  carried  on  simul- 
taneously. Moreover  the  most  profitable  portion  of  the  concrete,  the  short  haul 
portion,  is  done  first,  and  this,  combined  with  the  simultaneous  performance  of 
concreting  and  grading  operations,  insures  a large  payment  from  the  state  early  in 
the  life  of  the  job.  The  working  capital  generally  so  urgently  needed  at  the 
beginning  of  a job,  is  thus  provided. 

Two  methods  of  handling  a job  suitable  for  a one  mixer  plant  with  the 
unloading  point  at  or  near  the  middle  of  the  job,  are  in  general  use.  One  method 
is  to  start  grading  operations  at  the  point  nearest  the  material  yard,  and  work 
towards  either  end  of  the  road.  As  soon  as  a few  hundred  feet  of  subgrade  have 
been  prepared  mixing  operations  are  started,  and  follow  closely  behind  the  grading. 
Y/hen  the  mixer  reaches  one  end  of  the  job  it  is  brought  back  to  the  point  where  it 
first  started,  and  is  then  operated  towards  the  other  end.  All  of  the  track  used 
in  the  first  half  is  removed,  and  relaid  for  use  on  the  second  half.  This  plan 
permits  simultaneous  performance  of  concreting  and  grading  operations,  with  the 
attendant  advantages  pointed  out  in  the  preceding  paragraph.  It  is  necessary,  how- 
ever, to  bring  the  mixer  back  around  the  concrete  already  laid  after  it  reaches 
the  end  of  the  road,  in  order  to  permit  it  to  proceed  from  the  point  where  it  first 
started  to  the  other  end.  In  the  absence  of  suitable  side  roads,,  the  operation  of 
bringing  the  mixer  back  might  prove  to  be  impossible  or  extremely  difficult  without 
considerable  delay. 

Where  conditions  are  such  that  to  move  the  concrete  mixer  from  one  end 


52 


of  the  road  back  to  the  point  where  it  first  started  is  very  difficult,  or  im- 
possible, the  best  method  will  be  to  start  the  mixer  at  one  end  of  the  road  and 
operate  it  straight  thru  to  the  other.  The  disadvantage  of  this  plan  is  that  the 
laying  of  concrete  must  be  started  on  the  most  expensive  portion  of  the  road,  the 
long  haul  portion,  while  the  organization  is  inexperienced  and  the  track  is  not 
well  bedded.  It  is  frequently  necessary, also,  to  delay  concrete  operations  until 
all  of  the  grading  between  the  material  yard  and  one  end  of  the  road  is  completed. 

One  of  the  big  advantages  of  starting  the  mixer  at  the  point  of  minimum 
haul,  aside  from  the  large  payment  received  from  the  state  early  in  the  life  of 
the  job,  is  that  the  organization  is  experienced  by  the  time  the  most  difficult 
portion  of  the  work,  the  long  haul  portion,  is  reached.  By  this  time,also,all  of 
the  track  has  been  in  place  for  some  time,  and  is  well  bedded  and  surfaced.  When 
the  mixer  is  started  at  the  point  of  maximum  haul,  on  the  other  hand,  not  only 
must  the  inexperienced  organization  do  the  most  difficult  portion  of  the  work  first 
but  it  must  operate  over  a newly  laid  track  on  which  maximum  speed  cannot  be 
attained  for  some  time.  It  behooves  a contractor,  therefore,  to  weigh  carefully 
the  advantages  and  disadvantages  of  each  plan.  In  general  the  plan  of  starting 
the  mixer  at  the  point  of  minimum  haul  is  preferable,  and  should  be  followed  if 
at  all  practical. 

Either  of  the  foregoing  plans  of  operation  apply  whether  the  material 
yard  is  adjacent  to  the  road  under  construction, or  is  located  a mile  or  two  to  one 

side,  or  whether  the  material  yard  is  exactly  at  or  opposite  the  center  of  the 

job,  or  is  closer  to  one  end  than  to  the  other.  If  the  material  yard  is  located  at, 

or  opposite,  the  quarter  or  third  points,  the  second  of  the  two  foregoing  plans 

possess  less  disadvantages  than  if  the  material  yard  is  at,  or  opposite, the  oenter 
of  the  job,  for  in  such  a case  the  delay  in  starting  concreting  operations, due  to 
waiting  on  completion  of  the  grading, is  considerably  reduced. 


Sometimes  stone  must  be  received  at  one  end  of  a job  and  sand  at  the 
other,  while  cement  may  be  obtained  at  either  or  both  ends.  Such  a situation, 
while  about  the  most  difficult  in  highway  construction,  can  be  more  easily  handled 
by  light  railway  haulage  than  by  any  other  method.  Perhaps  the  best  way  of  illus- 
trating the  operation  of  such  a job,  is  by  describing  an  operation  planned  in 
Pennsylvania  in  1920.  A concrete  road  10  miles  long  was  to  be  constructed  in  an 
entirely  new  location,  through  very  rugged  country,  in  which  the  grading,  mostly 
shale,  averaged  some  15,000  cubic  yards  per  mile.  The  lowest  bid  received  was 
about  $105,000  per  mile,  which  gives  some  idea  of  the  character  of  the  work  in- 
volved. Sand  and  cement  were  available  at  the  railway  at  the  lower  end  of  the  job, 
while  stone  was  to  be  obtained  by  opening  up  a quarry  near  the  upper  end  of  the 
road.  The  sketch  below  shows  a straight  line  layout  of  the  road. 


/ 


53 


On  a job  of  this  kind  it  is  necessary  first  of  all  to  complete  the 
grading,  inasmuch  as  it  is  impossible  to  haul  material  from  one  end  to  the  other 
until  this  is  done.  The  amount  of  grading  on  this  road  is  sufficient  to  keep 
two  steam  shovel  outfits  busy  during  an  entire  working  season,  though  it  might  be 
possible  to  do  a good  deal  of  the  grading  in  the  winter  time  if  the  contract  was 
awarded  in  the  fall.  After  the  grading  was  completed,  in  case  any  method  of  haul- 
age  other  than  light  railway  was  employed,  it  would  be  necessary  to  place  on  the 
subgrade  all  the  stone  required,  before  mixing  operations  could  be  started.  The 
mixer  would  then  be  started  at  the  point  of  the  road  nearest  the  stone  supply,  and 
sand  and  cement  hauled  out  as  required.  It  is  obvious  that  once  the  laying  of 
concrete  had  begun,  it  would  be  impossible  to  haul  past  the  uncured  concrete  by 
any  other  method  than  light  railway  in  case  additional  stone  was  needed  to  re- 
plenish a shortage.  The  difficulty  of  distributing  just  the  proper  amount  of 
stone  is  obvious,  especially  in  view  of  the  fact  that  the  subgrade  must  be  trimmed 
by  hand  and  the  wheels  of  the  vehicles  hauling  material  will  out  up  the  subgrade 
considerably.  In  practice  a surplus  of  stone  would  probably  be  placed  on  the  sub- 
grade, in  order  to  prevent  the  likelihood  of  a shortage  and  delay  in  concreting. 
This  surplus  would  then  be  wasted  on  the  shoulder  of  the  road  from  time  to  time, 
because  it  would  be  uneconomical  to  stop  the  mixer  in  order  to  permit  of  salvage. 
Even  if  the  material  thrown  on  the  shoulder  of  the  road  could  be  salvaged  when  the 
pavement  was  completed,  the  cost  of  picking  it  up  and  shipping  it  to  another  point 
would  be  more  than  the  material  is  worth.  Not  only  would  this  method  of  operation 
involve  a considerable  wastage  of  stone,  but  to  haul  sand  and  cement  such  a long 
distance  over  the  subgrade,  obstructed  as  it  is  by  the  stone,  would  be  very  diffi- 
cult. On  this  particular  job  there  were  no  side  roads,  and  in  case  it  should  be- 
come necessary  to  haul  stone  to  replenish  a shortage,  it  would  be  necessary  to 
suspend  the  laying  of  concrete  until  all  of  the  pavement  already  laid  was  suffi- 
ciently cured  to  carry  traffic, In  case  any  other  method  of  haulage  than  light 
railway  were  used. 

The  combined  light  railway  and  motor  truck  method  of  operation  was  re- 
commended on  this  job,  renting  the  motor  trucks  very  cheaply  from  the  state.  With 
this  plan  of  operation,  as  with  any  other,  it  was  necessary  first  of  all  to  com- 
plete the  grading.  Inasmuch  as  bids  were  asked  in  the  early  spring,  the  con- 
tractor planned  to  devote  all  of  the  first  season  to  grading  by  means  of  two  steam 
shovels.  Just  before  freezing  weather  set  in, he  planned  to  drag  the  road  so  as  to 
put  it  in  fairly  smooth  condition  for  hauling.  During  the  winter  time  material 
was  to  be  hauled  by  motor  trucks  from  the  railroad  and  distributed  in  piles,  each 
pile  containing  sufficient  sand  to  build  one-fourth  to  one-half  mile  of  road, 
depending  upon  the  room  available.  The  mixer  was  to  be  started  at  the  end  of  the 
road  nearest  the  stone  supply,  and  about  two  miles  of  light  railway  track  laid  on 
the  shoulder.  Until  the  concrete  mixer  reached  the  end  of  the  track,  stone  could 
be  loaded  directly  into  batch  boxes  at  the  quarry  and  carried  by  the  train  to  the 
mixer.  As  the  train  passed  a sand  pile.  It  would  take  on  the  proper  amount  of  sand 
and  cement,  which  had  previously  been  placed  there.  The  sand  was  to  be  loaded  into 
a small  portable  bin  by  means  of  a bucket  elevator  and  a small  power  scraper,  and 
was  to  be  charged  directly  into  the  batch  boxes  as  they  passed  underneath  on  their 
way  to  the  mixer.  As  each  sand  pile  was  exhausted,the  bin  would  be  moved  on  to 
the  next  one.  By  the  time  the  mixer  reached  the  end  of  the  track,  a certain 
amount  of  the  concrete  would  be  sufficiently  cured  to  carry  traffic.  Motor  trucks 
would  then  be  used  to  haul  stone  from  the  quarry  over  the  finished  pavement  as  far 
as  specifications  permitted,  dumping  the  stone  on  the  pavement  near  a small  port- 
able bin.  This  bin  would  be  equipped  with  a bucket  elevator  and  a small  power 
scraper,  in  a manner  similar  to  the  sand  bin.  The  light  railway  trains  would  thus 
pass  under  the  stone  and  sand  bins  in  succession, and  take  on  the  proper  amounts  for 
each  batch.  As  the  concrete  hardened  the  stone  and  sand  bins  would  be  advanced 


« 


V 


f 


i 


54 


periodically,  and  the  track  no  longer  required  in  the  rear  picked  up  and  relaid 
in  advance  of  the  mixer.  If  desired, the  hauling  of  sand  could  "be  postponed  until 
shortly  before  the  laying  of  concrete  began.  Cement  would  be  hauled  out  and  stored 
at  each  sand  pile  just  in  advance  of  the  mixer.  In  case  an  improper  amount  of 
sand  was  stored  in  a pile, this  method  of  operation  would  enable  the  supply  to  be 
readily  replenished.  The  waste  of  stone,  involved  in  the  method  of  operation  des- 
cribed in  the  preceding  paragraph,  would  be  avoided  by  the  combined  light  railway 
and  motor  truck  method. 

With  a two  mixer  plant, we  can  so  plan  the  operation  as  to  produce  what 
is  known  as  a balanced  haul.  This  consists  of  starting  one  mixer  at  the  point  of 
minimum  haul,  and  the  other  mixer  simultaneously  at  the  point  of  maximum  haul* 

It  is  obvious  that  if  these  mixers  are  of  the  same  size,  they  should  operate  at 
approximately  the  same  rate  of  speed.  The  amount  of  equipment  released  by  the 
machine  which  started  at  the  point  of  maximum  haul,  as  its  haul  decreases,  is 
just  about  sufficient  to  make  up  the  shortage  constantly  occurring  at  the  mixer 
whose  haul  is  increasing.  If,  then,we  provide  sufficient  rolling  stock  for  two 
mixers  based  upon  the  point  of  average  haul,  we  will  have  sufficient  equipment  to 
supply  both  mixers  at  all  points  by  transferring  from  one  to  the  other  as  occasion 
arises.  With  a one  mixer  plant, we  are  confronted  by  the  problem  of  deciding  as  to 
just  what  length  of  haul  the  rolling  stock  should  be  proportioned  for.  If  we 
proportion  it  for  the  point  of  average  haul  we  will  have  an  insufficient  amount 
when  the  haul  exceeds  the  average,  while  if  we  proportion  it  for  the  point  of  maxi- 
mum haul  we  will  have  a surplus  as  soon  as  the  haul  is  less  than  the  maximum.  By 
operating  two  mixers  on  a balanced  haul,  however,  all  of  the  equipment  will  be 
kept  busy  at  all  times. 

Sometimes  it  i6  necessary  or  desirable  to  use  two  mixers  on  a road, 
where  the  unloading  point  is  located  at  one  end.  These  mixers  can  be  operated  on 
a balanced  haul  in  the  following  manner:  Start  both  mixers  at  the  center  of  the 

road,  operating  them  away  from  each  other  toward  opposite  ends  of  the  job.  Lay 
a line  of  track  for  each  mixer  on  opposite  shoulders  of  the  roai.  If  these  mixers 
are  of  the  same  capaoity, they  should  operate  at  about  the  same  rate  of  speed.  As 
one  mixer  approaches  the  material  yard, and  its  length  of  haul  decreases,  it  will 
release  track  and  rolling  stock  sufficient  to  make  up  the  constantly  occurring 
shortage  at  the  other  mixer, which  is  operating  away  from  the  material  yard.  This 
operation  is  continued  thruout  the  job,  the  surplus  equipment  released  by  one  mixer 
being  immediately  put  into  service  in  supplying  the  other.  This  plan  of  operation 
required  but  slightly  more  track  than  if  only  one  mixer  is  employed.  It  does, 
however,  involve  the  laying  and  removing  of  50  per  cent  greater  mileage  of  track, 
because  a line  of  track  equal  to  half  the  length  of  the  road  is  first  laid  on  each 
shoulder  after  whioh  the  track  on  one  shoulder  is  extended  to  the  far  end  of  the 
road.  The  sketoh  below  illustrates  an  operation  such  as  we  have  in  mind. 


55 


A job  suitable  for  a two  mixer  plant  with  an  unloading  point  at  or 
opposite  the  center  of  the  road,  is  one  frequently  seen  in  practice.  Such  a job 
is  well  adapted  to  the  application  of  a balanced  haul.  The  sketch  below  illus- 
trates a 10  mile  job  with  the  unloading  point  opposite  the  center  and  2 miles  away. 


Start  one  mixer  at  the  point  of  intersection  of  the  "dead  haul"  road 
with  the  10  mile  road,  the  point  of  minimum  haul,  and  the  other  mixer  and  the 
point  of  maximum  haul  at  the  end  of  the  road*  Operate  both  mixers  simultaneously 
in  the  same  direction,  transferring  equipment  from  one  to  the  other  as  occasion 
demands* 

A balanced  haul  can  be  applied  very  nicely  to  a job  with  unloading 
points  at  each  end,  by  starting  one  mixer  at  the  middle  of  the  job  and  the  other 
at  one  end.  The  mixers  should  be  operated  simultaneously  in  the  same  direction,and 
should  be  supplied  from  separate  material  yards*  The  layout  of  such  a road  is 
shown  in  the  following  sketch. 


Ai/ce  or  7-rrcx  — 

0s*  7-sV^rcj?  — * 

The  plan  of  operation  outlined  above  will  require  an  amount  of  track 
but  slightly  greater  than  half  the  length  of  the  road,  for  as  equipment  is  re- 
leased from  the  mixer  which  started  at  the  middle, it  is  transferred  to  the  mixer 
which  started  at  one  end.  This  plan  of  operation  requires  less  track  than  where 
all  the  material  must  be  hauled  from  one  end,  and  the  mileage  of  track  to  be  laid 
and  removed  is  equal  to  the  length  of  the  road.  The  operation  of  a two  mixer 
plant  with  a material  yard  at  each  end  of  the  road  involves  less  track  laying  and 
less  ton  mileage  than  where  all  material  must  be  hauled  from  one  end,  but  it 
necessitates  the  operation  of  two  material  yards.  Whether  it  is  more  economical 
to  establish  and  operate  two  material  yards  than  to  haul  all  material  from  one 
end,  depends  upon  the  decrease  in  the  ton  mileage  resulting  therefrom  and  must  be 
left  to  the  individual  judgment  of  the  contractor.  As  a rule,  unless  the  cost  of 
establishing  the  second  material  yard  is  excessive, it  will  generally  be  found 
that  the  saving  due  to  the  decreased  ton  mileage  and  the  decreased  amount  of  equij> 
ment  required  will  justify  two  yards. 

Still  another  method  of  operating  a two  mixer  plant  on  a balanced  haul 
when  all  material  must  be  hauled  from  one  end, is  by  starting  one  mixer  at  the  far 
end  of  the  road  and  the  other  at  the  end  nearest  the  material  yard*  Both  mixers 
should  be  operated  towards  the  center  of  the  job,  and  as  equipment  is  released 


56 


by  the  mixer  which  started  at  the  far  end  it  is  transferred  to  the  mixer  which 
started  at  the  near  end.  This  plan  possesses  no  particular  advantage  over  the 
plan  previously  described, of  starting  both  mixers  at  the  center  of  the  job  and 
working  them  away  from  each  other.  Track  for  supplying  each  mixer  should  prefer- 
ably be  laid  on  opposite  shoulders,  though  it  is  possible  for  a contractor  of  good 
organizing  ability  to  supply  both  mixers  from  one  line  of  track.  If  he  can  supply 
both  mixers  from  one  line  of  track,  he  will  save  the  cost  of  laying  and  removing 
an  amount  of  traok  equal  to  half  the  length  of  the  road. 

In  all  of  the  preceding  discussion  we  have  considered  only  the  complete 
railway  plant.  The  combined  light  railway  and  motor  truck  plant  can  be  applied 
in  much  the  same  way.  On  a job  suitable  for  a one  mixer  plant  with  the  material 
yard  at  one  end,  the  best  plan  of  operating  a combined  light  railway  and  motor 
truck  plant  is  to  start  the  mixer  at  the  point  of  minimum  haul,  as  soon  as  a few 
hundred  feet  of  subgrade  have  been  prepared.  If  the  material  yard  is  located 
directly  at  the  end  of  the  road,  material  can  be  hauled  by  light  railway  until  the 
mixer  reaches  the  end  of  the  l-l/2  miles  of  track  conmonly  employed  in  this  typeof 
plant.  If  the  material  yard  is  located  some  distance  from  the  beginning  of  the 
job,  material  can  be  hauled  in  batch  boxes  on  motor  trucks  to  the  beginning  of  the 
job, where  it  can  be  transferred  to  the  railway,  by  means  of  a portable  derrick, 
for  haul  to  the  mixer.  By  the  time  the  mixer  reaches  the  end  of  the  railway  track 
a certain  amount  of  the  pavement  already  laid  will  be  sufficiently  cured,  according 
to  specifications,  to  carry  traffic.  While  the  mixer  may  only  operate  20  days  per 
month,  or  say  two-thirds  of  the  time,  Sundays  and  holidays  and  other  days  during 
which  the  mixer  does  not  run  are  just  as  valuable  for  curing  concrete  as  are  work- 
ing days.  Each  day,  as  another  section  of  concrete  comes  of  age,  the  transfer 
point  is  advanced  by  dragging  forward  the  portable  derriok,  and  the  track  no  longer 
required  in  the  rear  is  relaid  in  advance  of  the  mixer.  If  the  mixer  operates  at 
an  average  of  400  feet  per  day,  the  transfer  point  can  be  advanced  at  approximately 
the  same  rate  daily.  The  advantage  of  this  plan  of  operation,  due  to  the  fact 
that  concreting  and  grading  can  be  carried  on  simultaneously,  has  been  previously 
pointed  out* 

A road  with  the  unloading  point  at  or  opposite  the  middle  of  the  job, 
or  some  point  between  the  middle  and  the  end,  can  be  handled  in  the  manner  out- 
lined in  the  previous  paragraph.  The  mixer  can  be  started  at  the  point  of  minimum 
haul  and  operated  away  from  the  material  yard  towards  one  end,  after  which  it  is 
brought  back  and  operated  towards  the  other  end,  or  it  can  start  at  one  end  of  the 
job  and  operate  continuously  thru  to  the  other  end. 

The  method  of  handling  a job  suitable  for  a one  mixer  plant  with  sand 
and  stone  at  opposite  ends, by  means  of  a combined  light  railway  and  motor  truck 
hauling  plant,  has  previously  been  outlined  in  describing  a 10  mile  road  in  Penn- 
sylvania. 

A two  mixer  plant  with  the  unloading  point  at  one  end  of  the  job,  can  be 
supplied  by  means  of  a combined  light  railway  and  motor  truck  plant  in  the  following 
manner*  Start  one  mixer  at  the  point  of  minimum  haul  and  the  other  mixer  at  the 
half  way  point,  supplying  1-1/2  miles  of  track  to  the  mixer  at  the  point  of  mini- 
mum haul  and  a length  of  track  equal  to  half  the  length  of  the  road  plus  I-1/2 
miles, to  the  mixer  at  the  half  way  point.  If  the  unloading  point  is  located 
exactly  at  the  end  of  the  job,  the  mixers  can  be  supplied  ty  means  of  light  railway 
haulage  entirely  until  they  reach  the  end  of  their  respective  tracks,  if  the 
unloading  point  is  some  distance  from  the  beginning  of  the  road,  material  can  be 
hauled  in  batch  boxes  on  motor  trucks  to  the  beginning  of  the  road  and  there 


J 


. 


57 


transferred  to  the  railway.  By  the  time  the  mixers  reach  the  end  of  their 
respective  lines  of  track,  a portion  of  the  concrete  already  laid  by  the  first 
mixer, operat ing  at  the  minimum  haul,  is  sufficiently  cured  to  carry  traffic. 

From  then  on  the  regular  method  of  operating  this  type  of  plant  is  followed, 
advancing  the  transfer  point  as  the  concrete  hardens  and  removing  track  in  the 
rear  and  relaying  it  in  advance  of  the  mixer.  The  plan  of  operation  just  des- 
cribed will  require  almost  as  much  track  as  if  a complete  railway  plant  were  used, 
and  there  is,  therefore,  no  particular  merit  in  it.  If  the  job  is  large  enough 
to  require  two  14-E  paving  mixers  and  it  is  still  desired  to  employ  the  combined 
light  railway  and  motor  truck  plant,  it  would  be  preferable  to  employ  a 28-E 
paver  rather  than  two  14-E’s.  A 28-E  operated  on  the  combined  principle  with  2 
miles  of  track, would  work  very  nicely. 

If  the  unloading  point  is  at,  or  opposite,  the  middle  of  the  job,  and  it 
is  desired  to  use  two  paving  mixers  supplied  by  the  combined  light  railway  and 
motor  truck  plant,  the  best  plan  would  be  to  start  both  mixers  at  the  point  of 
minimum  haul  and  operate  them  away  from  each  other  toward  opposite  ends  of  the 
road.  This  operat ion, in  effect,  is  exactly  the  same  as  if  two  separate  jobs  were 
operated  with  an  unloading  point  at  the  end. 

In  the  case  of  a job  with  an  unloading  point  at  each  end,  a two  mixer 
plant  can  be  operated  by  the  combined  light  railway  and  motor  truck  method  by 
starting  the  mixer  at  the  points  of  minimum  haul  and  operating  them  towards  each 
other  so  that  they  will  meet  in  the  middle.  The  regular  method  of  operation  with 
a combined  plant  will  be  in  effect  here. 

The  fundamental  idea  underlying  operation  with  a light  railway  haulage 
plant, or  a combined  light  railway  and  motor  truck  plantain  highway  construction, 
is  to  start  the  mixer  at  the  point  of  minimum  haul.  In  case  of  a two  mixer  plant 
start  one  mixer  at  the  point  of  minimum  haul  and  the  other  at  the  point  of  maxi- 
mum haul,  so  as  to  secure  a balanced  haul.  The  laying  of  concrete  can  then  be 
started  as  soon  as  a few  hundred  feet  of  subgrade  have  been  prepared,  thus  elimi- 
nating the  delay  that  generally  occurs  in  placing  concrete  due  to  the  necessity 
of  waiting  for  completion  of  the  grading,when  any  method  of  haulage  other  than 
light  railway  is  used.  Not  only  is  this  delay  eliminated,  but  the  laying  of  con- 
crete and  grading  can  be  performed  simultaneously.  The  most  profitable  portion 
of  the  concrete,  the  short  haul  portion,  can  be  done  first,  and  this,  in  conjunc- 
tion with  the  simultaneous  performance  of  concreting  and  grading,  insures  a large 
payment  from  the  state  early  in  the  life  of  the  job.  The  working  capital,  always 
so  badly  needed  at  the  start  of  a job,  is  thus  provided.  By  starting  the  mixer 
at  the  point  of  minimum  haul  the  organization  is  experienced  by  the  time  the  most 
difficult  portion  of  the  work,  the  long  haul  portion,  is  reached,  and  the  track 
is  well  bedded. 

ViTith  either  the  complete  railway  system  or  the  combined  light  railway 
and  motor  truck  system,  all  hauling  is  done  over  steel  rails  or  improved  roads. 
Delay  due  to  rain  should  thus  be  reduced  to  a minimum.  Of  course, when  the  unload- 
ing point  is  located  some  distance  from  the  road  under  construction  and  the  com- 
bined system  is  used,  the  road  leading  from  the  unloading  point  is  not  always  of 
the  best.  Operation  over  this  road,  hov/ever,  is  no  more  serious  than  if  some  other 
method  of  haulage  were  used,  and  the  cutting  up  of  it  is  by  no  means  as  serious  or 
costly  to  the  contractor  as  is  the  cutting  up  of  the  subgrade. 


58 


CHAPTER  IX. 


HAULAGE  EQUIPMENT  REQUIRED. 


In  this  chapter  we  will  consider  all  of  the  light  railway  rolling  stock 
and  the  necessary  amount  of  track  and  passing  sidings  required,  as  well  as  all 
motor  truck  equipment  used  in  conjunction  with  the  light  railway  in  a combined 
light  railway  and  motor  truck  plant. 

The  rolling  stock  and  track  required,  varies  not  with  the  length  of  the 
road  but  with  the  length  of  haul.  In  case  of  a 10  or  12  mile  job,  it  is  generally 
possible  to  establish  unloading  points  so  that  not  more  than  3 or  4 miles  of  track 
are  needed.  When  the  unloading  point  is  located  at  one  end,  however,  it  is  nec- 
essary to  use  an  amount  of  track  equal  in  length  to  that  of  the  road,  except  where 
the  combined  system  of  haulage  is  employed. 

In  proportioning  the  amount  of  rolling  stook,  except  in  case  of  a 
balanced  haul,  we  are  confronted  with  the  problem  of  basing  our  computations  on  the 
average  haul,  on  the  maximum  haul,  or  on  some  point  in  between.  If  we  adopt  the 
average  haul  as  the  basis  for  the  rolling  stock  required,  we  will  have  an  insuffi- 
cient amount  as  soon  as  the  haul  exceeds  the  average.  The  capacity  of  the  haulage 
plant  between  the  points  of  average  and  maximum  haul,  in  such  a case,  is  insufficient 
to  supply  the  mixer  at  the  proper  rate.  If  we  base  the  amount  of  rolling  stock 
upon  the  maximum  haul,  on  the  other  hand,  we  will  have  a surplus  on  all  hauls  be- 
low the  maximum.  This  will  insure  operation  of  the  concrete  mixer  at  full  capa- 
city at  all  times,  but  the  method  is  uneconomical  due  to  the  surplus  rolling  stock 
which  is  idle  a good  deal  of  the  time.  Experience  indicates  that  a length  of  haul 
about  half  way  between  the  average  and  the  maximum,  is  the  proper  one  upon  which 
to  base  the  rolling  stock  required.  In  other  words, when  material  must  be  hauled 
from  one  end  of  a job  to  supply  a single  mixing  plant,  proportion  the  rolling 
stock  upon  a basis  of  three-fourths  of  the  maximum  haul. 

Experience  has  demonstrated  that  an  average  speed  of  6 miles  an  hour  for 
both  loaded  and  empty  trains,  is  the  proper  speed  to  use  in  determining  the  amount 
of  rolling  stock  needed  to  supply  the  mixer.  In  rolling  country, where  the  down 
grades  balance  the  up  grades  fairly  well  in  both  degree  and  length,  this  average 
speed  of  6 miles  per  hour  can  also  be  used  in  making  rolling  stock  computations. 

In  special  cases,  where  the  preponderance  of  asoending  grades  is  opposed  to  the 
loaded  trains,  it  might  be  necessary  to  compute  the  weighted  mean  speed  as  des- 
cribed in  a previous  chapter. 

In  operating  a light  railway  plant  some  contractors  prefer  to  keep  the 
locomotive  attaohed  to  the  train,while  it  is  being  unloaded  at  the  mixer  and  loaded 
at  the  material  yard.  Other  contractors  prefer  to  detach  the  locomotive  and 
immediately  pick  up  another  train.  The  decision  as  to  which  method  to  adopt  de- 
pends upon  local  conditions,  and  frequently  both  methods  are  used  in  the  same  job. 
Where  long  trains  of  10  to  20  cars  are  used, it  is  generally  more  economical  to 
detach  the  locomotive  at  the  mixer  and  return  at  once  to  the  material  yard,  in 
such  a case  the  train  at  the  mixer  is  moved  by  means  of  a team  of  horses,  the  road 
roller,  or  by  hand.  Where  small  trains  of  only  3 or  4 cars  are  used,  it  is  gen- 
erally preferable  to  keep  the  locomotive  attached  to  the  train  at  the  mixer  during 
the  unloading  process,  except  where  the  split  train  method  is  used.  Even  in  hilly 
country  it  is  seldom  necessary  to  use  such  small  trains,  except  for  a small  pro- 
portion of  the  time* 


59 


LOCOMOTIVE  ATTACHED  TO  TRAIN  AT  MIXER 

The  question  of  whether  to  detach  the  locomotive  from  the  train  at  the 
material  yard  during  the  loading  process,  is  governed  by  the  same  conditions  as  at 
the  mixer.  When  the  tunnel  system  of  storage  is  used,  the  switching  of  the  train 
at  the  material  yard  is  frequently  effected  by  means  of  a small  hoisting  engine 
set  at  one  end  of  the  tunnel  • Sometimes  an  endless  cable  is  passed  thru  the 
tunnel, and  around  sheaves  so  as  to  pass  outside  of  the  material  pile.  A team 
hitched  to  this  cable  on  the  outside  can  then  be  used  to  shift  the  train  in  the 
tunnel.  Many  tunnels  are  constructed  on  a slight  grade,  about  one-half  of  1 per 
cent,  so  that  the  shifting  of  the  train  is  facilitated  thereby.  Experience  has 
shown  that  where  the  tunnel  system  of  storage  is  used,  an  allowance  of  one  minute 
per  batch  is  sufficient  for  completely  charging  a train  at  the  material  yard.  To 
load  a 10  car, 20  batoh  train,  therefore,  will  require  20  minutes,  and  in  computing 
the  running  time  of  a locomotive, which  remains  attached  to  the  train  during  load- 
ing, this  allowance  should  be  made. 

When  material  is  hauled  from  one  end  of  a job  to  a one  mixer  plant,  the 
rolling  equipment  is  generally  based  upon  three-fourths  of  the  maximum  haul.  On 
all  hauls  less  than  three-fourths  of  the  maximum,  a surplus  of  rolling  equipment 
will  be  on  hand,  and  during  this  period  it  is  generally  feasible  to  keep  the  loco- 
motive attached  to  the  train  at  the  mixer  during  the  unloading  process,  if  desired. 
Later  on,  as  the  haul  increases  to  the  point  where  time  is  not  available  for  keep- 
ing the  locomotive  at  the  mixer  or  at  the  material  yard  during  the  unloading  and 
loading  process,  the  locomotive  can  be  detached  from  the  train  at  one  of  these 
points.  Still  later  on  as  the  length  of  haul  increases,  it  will  probably  be  nec- 
essary to  detach  the  locomotive  from  the  train  at  both  the  mixer  and  the  material 
yard. 

If  the  locomotive  is  detaohed  at  the  mixer  and  at  the  material  yard, 
fita  additional  train  of  cars  must  be  provided  at  each  point.  For  instance,  if  only 
3 locomotives  are  in  use  and  they  remain  attached  to  the  trains  during  all  opera- 
tions, but  3 trains  are  required.  If  the  trains  are  dropped  at  the  mixer  and  the 
material  yard,  however,  an  additional  train  must  be  provided  at  each  of  these 
points,  making  5 all  told.  In  considering  the  question  of  detaohing  locomotives 
at  the  mixer  and  at  the  material  yard,  the  cost  of  additional  cars  and  the  cost  of 
switching  by  means  of  team,  hoisting  engine,  or  by  hand,  must  be  compared  to  the 


60 


oost  of  the  additional  locomotives  which  might  he  required  and  their  cost  of  oper- 
ation. In  the  majority  of  cases  it  is  more  economical,  as  a rule,  to  detach  the 
locomotives  from  the  train  at  the  mixer  and  the  material  yard,  than  it  is  to  keep 
them  there  during  the  process  of  unloading  and  loading.  Where  6 ton  locomotives 
are  used  for  hauling,  3 ton  machines  are  sometimes  provided  for  switching  trains 
at  the  mixer  and  at  the  material  yard. 

In  charging  the  mixer  by  means  of  batch  boxes  carried  on  oars,  it  is 
necessary  to  move  the  car  for  each  batch  so  as  to  permit  clearance  when  the  mixer 
derrick  picks  up  a box.  In  level  country  the  problem  of  moving  cars  is  not 
serious,  and  is  almost  always  done  by  hand  by  detaching  and  moving  one  car  at  a 
time.  A single  horse  is  sometimes  used  to  haul  the  empty  cars  to  the  switch, 
which  is  never  more  than  a few  hundred  feet  from  the  mixer.  As  a rule,  however, 
the  passing  siding  is  kept  close  to  the  mixer,  not  more  than  one-half  or  one  day’s 
run  away,  and  the  locomotive  arriving  with  the  loaded  train  has  plenty  of  time  to 
switch  the  empty. 


SWITCHING-  CARS  WITH  A HORSE 


61 


PASSING  SIDING  NEAR  MIXER 


In  hilly  country  the  problem  of  switching  cars  at  the  mixer  is  somewhat 
more  difficult  than  in  level  country/ due  to  the  grades.  When  the  locomotive  is 
detached  from  the  train  at  the  mixer,  the  train  should  be  left  standing  on  the 
up-hill  side  of  the  mixer.  Cars  used  in  hilly  country  are  generally  all  equipped 
with  brakes,  and  they  can  be  let  down  to  position  near  the  mixer  either  singly  or 
in  trains.  Single  cars  can  easily  be  controlled  by  means  of  their  brakes,  or  by 
means  of  a stick  of  wood  pressed  against  a wheel.  After  being  unloaded  the  cars 
are  dropped  down  grade  some  distance,  where  they  are  again  formed  into  a train  at 
a siding.  When  it  is  desired  to  switch  entire  trains  on  steep  grades  in  order  to 
permit  unloading,  some  other  method  of  control  than  brakes  must  generally  be  used. 
This  is  due  to  the  fact  that  the  brakes  on  each  car  operate  independently  of  the' 
other,,  and  there  is  no  means  of  controlling  all  the  brakes  in  a train  as  a unit. 

A method  frequently  used, in  such  a case,  is  to  "snub"  a rope  around  a tree  or  an 
anchor  post  at  one  side  of  the  track,  pass  it  thru  a sheave  in  the  center  of  the 
track,  and  attach  it  to  the  train.  Still  another  method  of  shifting  trains  as  a 
unit  on  grade, is  by  means  of  a line  attached  to  the  road  roller.  The  passing  sid- 
ing should  always  be  placed  on  the  down  grade  side  of  the  mixer,  so  as  to  permit 
the  empty  cars  to  be  coasted  down  to  the  siding  and  there  formed  into  a train. 

Consider  now  a road  5 miles  long,  with  an  unloading  point  at  one  end. 

The  amount  of  track  required  is  equal  to  6 miles,  plus  a certain  amount  for  passing 
sidings  and  for  the  material  yard.  The  amount  of  track  needed  for  passing  sidings 
cannot  be  determined  until  the  number  of  sidings  are  known,  and  this  in  turn  de- 
pends upon  the  number  and  size  of  trains.  As  a rule,  however,  a passing  siding 
every  mile  is  sufficient  where  but  one  mixer  is  to  be  supplied.  The  length  of 
passing  siding  depends  upon  the  size  of  trains.  The  overall  length  of  a car  from 
coupling  to  coupling  is  about  8 feet,  so  that  a 10  car  train  with  a locomotive 
will  require  about  90  feet  in  the  clear.  To  allow  a little  extra  we  will  provide 
105  feet  of  clear  track  in  the  siding,  inasmuch  as  this  is  exactly  equal  to  7 sec- 
tions of  track.  In  case  it  is  desired  to  determine  the  exact  number  of  sidings 
necessary,  a time  schedule  should  be  computed  and  a graphical  determination  made 
from  it.  In  the  case  in  point,  we  will  provide  one  passing  siding  at  the  mixer  and 
4 along  the  line.  At  the  mixer  we  will  provide  795  feet  of  track,  inasmuch  as  this 
is  exactly  equal  to  53  sections.  The  total  amount  of  track  provided  on  this  job, 
therefore,  will  equal  5.25  miles. 


JJ 


. 


62 


The  switch  and  a special  straight  and  curved  section  required  to  fonn 
one  end  of  a passing  siding,  is  known  as  a half  turnout.  Two  of  these  are  re- 
quired at  each  passing  siding,  while  at  the  material  yard  we  will  provide  4 more. 
This  makes  a total  of  14  half  turnouts  all  told  on  this  job.  Details  of  a half 
turnout  will  be  found  on  page  24  of  bulletin  #29-D  of  The  Lakewood  Engineering 
Company,  which  is  included  in  the  appendix. 

Special  curved  sections  7-l/2  feet  in  length  of  30  foot  radius  are  pro- 
vided, 6 of  which  will  subtend  a central  angle  of  88  degrees  and  45  minutes. 

Curves  of  lesser  degree  can  be  obtained  by  using  fewer  curved  sections.  The  number 
of  curved  sections  to  be  provided  on  a job  depends  upon  local  conditions.  In  this 
case  we  will  assume  one  90  degree  bend  in  the  road,  and  at  the  material  yard  3 more 
It  is  necessary,  therefore,  to  provide  about  25  curved  sections  for  this  job. 

The  rolling  stock  will  be  based  upon  a haul  of  three-fourths  of  the 
maximum,  or  3*75  miles,  and  upon  a speed  of  6 miles  per  hour.  An  allowance  of  5 
minutes  will  be  made  for  switching  trains  at  the  mixer,  and  th&  same  amount  of  tine 
at  the  material  yard.  The  controlling  grade  will  be  assumed  at  3 per  cent,  en- 
abling a 6 ton  looomotive  to  haul  a train  of  7 to  8 cars,  each  carrying  2-4  bag 
batches  of  material  for  1-2-3  concrete.  Such  a oar  will  weigh  3.4  tons,  with 
sand  at  3,000  pounds  per  cubic  yard,  stone  at  2,700  pounds  per  cubic  yard,  and 
cement  at  374  pounds  per  barrel. 

The  running  time  of  the  train,  based  upon  the  foregoing  data,  will  be 
85  minutes  per  round  trip  on  a 3.75  mile  haul.  This  is  equivalent  to  7 round 
trips  per  10  hour  day,  enabling  each  locomotive  to  deliver  98  batches  to  the 
mixer.  Three  locomotives  are,  therefore,  required  to  supply  the  mixer  with  300 
batches  per  day.  Five  trains  of  7 cars  eaoh,  or  a total  of  35  cars  and  70  batch 
boxes,  must  be  provided. 

The  amount  and  cost  of  the  railway  equipment  needed  on  a job  of  this 
kind,  based  upon  prices  in  March,1921,  is  as  follows: 

EQUIPMENT 

5^:  miles  straight  track  @ $6,318.40 
14  half  turnouts  @ $150.00 
25  curved  sections  @ $13.95 
35  batch  box  cars  @ $115.00 
70  batch  boxes,  25  cu.ft.  cap.  @ $71.20 
3-6  ton  gasolene  locomotives  <3$4, 600.00 
2 platform  cars,  general  utility,  $ $415.00 


COST 

WEIGHT 

$33,171.60 

637,560 

lbs 

2,100.00 

15,190 

*t 

348.75 

4,625 

it 

4,025.00 

38,500 

tt 

4,984.00 

28,000 

tt 

13,800.00 

37,300 

tt 

830.00 

4.000 

« 

$59,259.35 

765,175 

lbs, 

The  sketch  below  shows  a road  on  which  it  is  desired  to  operate  two 
paving  mixers,  supplying  them  by  means  of  a complete  railway  haulage  plant  from  an 
unloading  point  at  one  end.  The  mixers  will  be  operated  on  the  balanced  haul 
principal,  by  starting  at  the  center  of  the  road  and  working  away  from  each  other 
toward  each  end.  Inasmuch  as  these  mixers  are  of  the  same  size,  the  rate  of  oper- 
ation of  each  should  be  about  the  same.  The  equipment  released  by  the  mixer  oper- 
ating on  the  decreasing  haul,  therefore,  should  be  just  about  sufficient  to  pro- 
vide for  the  shortage  at  the  mixer  operating  on  the  increasing  haul.  Rolling 
stock  provided  for  two  mixers  at  the  point  of  average  haul,  therefore,  should  be 
sufficient  to  keep  each  mixer  fully  supplied  at  all  times  by  transferring  from  one 
to  the  other  as  occasion  requires. 


63 


The  amount  of  track  required  for  the  two  mixer  plant,  is  slightly  more 
than  twice  that  for  the  one  mixer  plant  previously  considered.  This  is  "because 
a small  amount  of  extra  track  is  provided/to  take  care  of  delay  in  moving  equip- 
ment from  one  mixer  to  the  other.  We  will  allow  an  extra  quarter  mile  for  this 
purpose,  making  a total  of  10-3/4  miles  required  for  this  job.  The  rolling  stock 
will  be  based  upon  the  full  haul  of  5 miles,  rather  than  three-fourths  of  5 miles 
as  in  the  single  mixer  job. 

Five  passing  sidings  will  be  provided  for  each  mixer,  making  a total  of 
24  half  turnouts, including  4 at  the  material  yard.  Assuming  one  90  degree  bend  in 
the  road  and  3 at  the  material  yard,  a total  of  30  curved  sections  are  needed. 

The  running  time  of  a locomotive  per  round  trip  on  the  5 mile  average 
haul  at  6 miles  per  hour,  allowing  5 minutes  for  switching  trains  at  the  mixer  and 
5 minutes  at  the  material  yard,  is  110  minutes.  This  is  at  the  rate  of  5 round 
trips  per  10  hour  day.  Assuming  an  8 car  train,  each  locomotive  will  deliver 
80  batches  per  day  to  the  mixer  so  that  4 locomotives  are  needed  to  supply  at 
least  300  batches.  Six  trains  of  8 cars  each  and  16  batch  boxes  must  be  assigned 
to  each  mixer,  and  the  total  amount  of  equipment  required  for  two  mixers  would  be 
approximately  twice  that  required  for  one.  Inasmuch  as  4 locomotives  and  6 trains 
possess  somewhat  greater  hauling  capacity  than  is  required  by  one  mixer,  we  will 
provide  a total  of  7 looomotives  and  11  trains  for  two  mixers  instead  of  doubling 
the  amount  required  for  one. 

In  addition  to  the  equipment  listed  in  the  foregoing,  it  is  necessary 
to  provide  at  least  2 double  truck  platform  cars  for  the  purpose  of  moving  track 
from  one  mixer  to  the  other  and  for  general  utility  haulage.  The  oost  of  the 
plant  outlined  for  the  two  mixer  job  shown  in  the  sketch  above,  can  be  computed 
as  in  the  previous  example.  When  mixers  are  operated  on  the  balanced  haul  they 
can  be  operated  at  a full  rate  of  speed  at  all  times,  due  to  the  fact  that  track 
and  rolling  stock  can  be  transferred  from  one  to  the  other  as  desired.  Further- 
more, the  rolling  stock  is  kept  busy  at  all  times,  and  the  problem  of  a surplus  or 
a shortage  of  haulage  equipment  is  eliminated.  The  investment  in  haulage  equip- 
ment per  mixer  is  less  when  mixers  are  operated  on  a balance  haul,  than  where  but 
one  mixer  is  to  be  supplied.  £his  is  obvious  when  we  consider  that  haulage  equip- 
ment for  a one  mixer  plant  is  based  upon  a length  of  haul  equal  to  three-fourths 
of  the  maximum,  while  haulage  equipment  for  a mixer  operating  on  a balanced  haul 
is  based  upon  the  average  haul. 

A two  mixer  p]ant  with  the  unloading  point  near  the  middle  of  the  job 
and  immediately  adjacent  to  or  some  distance  from  the  road,  can  be  operated  very 
nicely  on  the  balanced  haul  principle.  Less  track  is  required  in  such  a case, 
then  where  all  material  must  be  hauled  from  one  end.  The  most  expensive  type  of 
operation  is  that  where  all  material  must  be  hauled  from  one  end  of  the  job.  If 
possible  an  unloading  point  should  be  secured  as  near  the  center  of  the  job  as 
conditions  will  permit,  for  the  investment  in  haulage  equipmait,  as  well  as  the 
ton  mileage,  is  thereby  considerably  reduced. 


64. 


GENERAL  UTILITY  PLATFORM  CAR 


The  fundamental  idea  to  be  kept  in  mind  in  operating  mixers  upon  the 
balanced  haul  principle,  is  that  equipment  should  be  based  upon  the  average  haul* 
The  amount  of  equipment  required  for  two  mixers  is,  therefore,  approximately  twice 
that  required  for  one.  The  investment  in  haulage  equipment  per  mixer  is  less 
in  a two  mixer  plant  operating  upon  a balanced  haul,  than  in  a one  mixer  plant. 

The  general  characteristics  of  a combined  light  railway  and  motor  truck 
haulage  plant  for  highway  construction,  have  already  been  described.  The  funda- 
mental idea  of  this  plan  of  operation  is  to  haul  material  by  motor  truck  over 
that  portion  of  the  oonorete  which,  according  to  specifications,  is  suf f iciently 
cured  to  carry  traffic,  and  to  transfer  material  at  this  point  to  a light  railway 
train  for  haul  past  the  uncured  concrete  to  the  mixer. 

A good  organization  with  an  adequate  supply  of  materials,  should  lay 
about  400  feet  of  18  foot  concrete  road  per  10  hour  day  with  a 14-E  mixer.  In 
a normal  season  about  20  working  days  per  month  should  be  obtained,  and  at  this 
rate  14  working  days  should  be  obtained  during  the  21  day  curing  period  which 
most  states  require  before  permitting  traffic  on  the  concrete.  At  a rate  of  400 
feet  per  day,  the  mixer  should  lay  about  5,600  feet  of  road  in  14  working  days. 

The  minimum  amount  of  track  that  must  be  provided  for  hauling  material  from  the 
transfer  point  to  the  mixer  is,  therefore,  5,600  feet 4 To  allow  for  failure  to 
move  up  track  promptly,  slow  curing  of  concrete,  or  for  more  than  14  working  days 
during  the  21  day  curing  period,  it  is  wise  to  provide  1-1 Jz  miles  of  track  for 
a oombined  light  railway  and  motor  truck  haulage  plant. 

Two  passing  sidings,  one  at  the  transfer  point  and  one  near  the  mixer, 
will  be  sufficient,  so  4 half  turnouts  must  be  provided.  The  number  of  curved 
sections  will  depend  upon  each  individual  road,  but  in  this  case  we  will  assume 
10  sections  to  be  sufficient. 

A 5 ton  motor  truck  will  carry  4 batch  boxes,  each  containing  properly 
proportioned  materials  for  a 4 bag  batch  of  the  mixture  generally  specified  in 
concrete  road  work,  while  a 3-l/2  ton  truck  will  carry  3 such  batches.  A suffi- 
cient number  of  batch  boxes  must  be  provided  to  equip  the  maximum  number  of  trucks 
needed  at  the  maximum  haul. 


22" 


65. 


BATCH  BOX  HAULAGE  WITH  3-l/2  TON  THJCK 


In  determining  the  amount  oaf  motor  truck  equipment  needed,  a speed  of 
6 miles  per  hour  loaded  and  10  miles  per  hour  empty  is  a good  average  over  earth 
or  macadam  roads  in  fairly  good  condition*  On  hard  surfaced  roads,  an  average 
speed  of  10  miles  per  hour  for  a 5 ton  truck  "both  loaded  and  empty  is  about  right. 
Experience  has  shown  that  an  allowance  of  5 minutes  at  the  material  yard  for  load- 
ing 4 batch  boxes  and  10  minutes  at  the  transfer  point,  is  ample. 


LOADING  TRUCK,  BATCH  BOX  HAULAGE  SYSTEM 


/ A7/z.£ 


Ck, 


-4. 


—A7/X3*  /4-  -£ 


& ,CT.  CT£>*s<0*37~.£ 


/?/&£.  4 ro//W 

'y&rtD  ' z^7-  S7-/7^7-  or  003 


/£  - 


>// a ss  or  7~rrcrzi. 


£OA73//V£D  L/GttT  /?/?/LW/7y  /7/VO  T/7UC/<  5ySJ-£/Y7. 


•I 


66 


TRANSFERRING  BATCH  BOXES  FROM  TRUCK  TO  CAES 


The  sketch  at  the  Bottom  of  page  65  shows  the  layout  for  a combined 
light  railway  and  motor  truck  haulage  plant  applied  to  a 5 mile  job,  the  unload- 
ing point  for  which  is  located  1 mile  from  one  end.  The  best  plan  of  operation 
is  to  start  the  mixer  at  the  end  of  the  road  nearest  the  unloading  point,  as  shown 
in  the  sketch.  Loaded  batch  boxes  will  be  hauled  by  motor  truck  to  the  beginning 
of  the  job,  where  they  will  be  transferred  to  light  railway  cars  by  means  of  a 
small  crane  shown  in  the  photograph  above,  or  By  means  of  a portable  derrick 
shown  in  illustration  below. 


PORTABLE  DERRICK  FOR  TRANSFERRING  BATCH  BOXES 

The  transfer  point  will  be  maintained  at  the  beginning  of  the  job  until 
the  mixer,  which  operates  at  about  1.E5  miles  per  month,  is  near  the  end  of  the 
track.  By  this  time  about  half  of  the  concrete  laid  is  21  days  old.  The  transfer 
point  will  then  be  advanced  as  far  as  possible  by  moving  up  the  portable  derrick, 
and  the  track  no  longer  required  in  the  rear  will  be  picked  up  and  relaid  in  ad- 
vance of  the  mixer.  This  operation  will  be  repeated  each  day, or  every  two  days, 
as  additional  concrete  comes  of  proper  age  to  carry  traffic. 

We  will  assume  that  the  road  between  the  material  yard  and  the  beginning 
of  the  job  is  not  improved,  so  that  an  average  speed  of  6 miles  per  hour  loaded 
and  10  miles  per  hour  empty  is  all  that  can  be  expected  from  the  trucks.  At  this 
rate,  allowing  5 minutes  for  loading  and  10  minutes  for  transferring,  the  round 
trip  on  the  1 mile  haul  will  be  performed  in  31  minutes.  This  is  at  the  rate  of 


i 


i\ 


67 


19  round  trips  per  10  hour  day,  and  inasmuch  as  each  5 ton  truck  carries  4 batches^ 
it  will  deliver  76  hatches  per  day  to  the  transfer  point.  To  provide  a supply  of 
300  batches,  will  require  the  services  of  4 trucks. 

The  maximum  haul  for  trucks  will  be  l-l/2  miles  from  the  far  end  of  the 
road,  or  a distance  of  4-l/2  miles.  On  the  first  mile  of  haul  the  loaded  truck 
will  average  a speed  of  6 miles  per  hour,  and  on  the  remaining  3-l/2  miles  over 
the  finished  pavement  it  will  average  10  miles  per  hour.  On  the  return  trip  an 
average  speed  of  10  miles  per  hour  should  be  attained  thruout.  Allowing  5 minutes 
for  loading  and  10  minutes  for  transferring,  a total  of  73  minutes  are  required 
per  round  trip  on  the  maximum  truck  haul.  At  this  rate  a truck  will  make  6 round 
trips  per  day,  delivering  32  batches  to  the  transfer  point.  On  the  maximum  haul, 
therefore,  9 trucks  should  suffice,  making  an  average  of  6 to  7 trucks  thruout  the 
job. 

On  the  motor  truck  portion  of  a combined  light  railway  and  motor  truck 
haul,  it  is  generally  more  economical  for  a contractor  to  rent  trucks  than  to 
purchase  them.  He  can  then  add  trucks  from  time  to  time  as  needed.  A contractor 
must  distribute  all  his  plant  charges  over  a working  season  of  only  some  120  days, 
whereas  a trucking  company  can  distribute  its  plant  charges  over  a period  twice  as 
long.  For  this  reason  the  trucking  company  can  afford  to  rent  trucks  at  a smaller 
per  diem  rate,  than  the  contractor  can  operate  his  own  trucks  for. 

Inasmuch  as  a maximum  of  about  9 trucks  are  required  on  this  job  and 
each  truck  carries  4 boxes,  36  batch  boxes  must  be  provided  for  the  trucks.  For 
contingency  4 more  should  be  added,  making  a total  of  40  in  addition  to  those 
required  by  the  railway  cars. 


On  the  railway  portion  of  a combined  light  railway  and  motor  truck  haul, 
the  locomotive  operates  continually  between  the  transfer  point  and  the  mixer  on 
an  average  haul  of  about  1 mile.  At  a speed  of  6 miles  per  hour,  allowing  5 min- 
utes at  the  mixer  and  at  the  transfer  point  for  switching  purposes,  30  minutes  are 
required  by  the  locomotive  to  make  a round  trip.  During  this  30  minutes  the  mixer 
will  consume  about  15  batches  of  material,  so  that  a train  of  7 or  8 cars  must  be 


used.  In  case  the  grades  are  so  steep  that  a train  of  only  half  this  size  can  be 
used,  it  will  be  necessary  to  provide  2 locomotives.  Each  locomotive  can  then 
haul  a train  of  4 cars,  or  they  can  cooperate  in  hauling  a train  of  8 cars.  Fewer 


EQUIPMENT 

1 6^-ton  gasolene  locomotive 
24  batch  box  cars  @$115.00 
48  batch  boxes  for  cars  @ $71.20 
40  batch  boxes  for  trucks  @ $71.20 
1st  mile  straight  track  @ $6,318.40 
4 half  turnouts  @ $150.00 
10  curved  sections  @ $13.95 
1 platform  car,  general  utility 


3 car  trains, 
can  be  used. 

In  the 

case 

COST 

WEIGHT 

$ 4,600.00 

12,500 

lbs. 

2,760.00 

26,400 

i» 

3,417.60 

19,200 

it 

2,848.00 

16,000 

It 

9,477.60 

182,160 

n 

600.00 

4,320 

n 

139.50 

1,850 

It 

415.00 

2.000 

ft 

$24,257.70 

264,430 

lbs. 

The  cost  of  equipment  shown  in  the  foregoing  table  is  the  current  cost 
in  Maroh,  1921. 


1 


* 


68 


LOCOMOTIVE  AT  TRANSFER  POINT 


TRAIN  APPROACHING  MIXER,  COMBINED  SYSTEM 


Sometimes  material  is  hauled  in  tnilis:  in  dump  body  trucks,  on  the  motor 
truck  portion  of  a combined  light  railvgay  and  motor  truck  plant.  In  such  a case 
material  is  dumped  near  a small  portable  bin  at  the  transfer  point,  into  which  it 
is  rehandled  by  means  of  a bucket  elevator  and  a power  scraper,  a small  crane 
equipped  with  a clam  shell  bucket,  or  a portable  belt  conveyor.  The  batoh  box 
system  of  haulage  is  preferable  to  the  bulk  system,  because  not  only  are  all  pro- 
portioning operations  concentrated  at  the  material  yard  but  a light  derrick  can  be 
substituted  for  the  expensive  rehandling  equipment  necessitated  at  the  transfer 
point  by  the  bulk  system.  Sometimes  it  is  necessary  to  employ  the  bulk  system  , 
where  the  sand,  cement,  and  stone  are  obtained  at  widely  scattered  points.  Even 
when  the  bulk  system  of  haulage  must  be  resorted  to,  the  combined  light  railway  and 
motor  truck  plan  possesses  big  advantages  over  the  method  of  dumping  material  on 
the  subgrade  or  of  charging  the  mixer  direct  from  a truck. 


Sometimes  the  batch  box  system  of  haulage  is  objected  to,  on  the  grounds 
of  the  dead  weight  of  the  boxes.  It  must  be  kept  in  mind,  however,  that  the  batch 


69 


1 


■box  system  permits  a platform  truck  or  a plain  truck  chassis  equipped  with  a 
light  wooden  frame,  to  be  employed  as  haulage  units.  Hot  only  does  this  reduce 
the  cost  of  rental  or  purchase  of  trucks,  but  it  increases  the  number  of  units 
available.  Four  steel  batch  boxes  of  sufficient  capacity  to  contain  a 4 -bag 
batch  of  material  for  the  mixtures  commonly  employed  in  concrete  road  construction, 
will  weigh  1,800  pounds  and  cost  about  $280.00.  The  dump -body  for  a 5-ton  truck 
will  weigh  about  2,000  pounds,  and  will  cost  about  $800.00.  In  both  weight  and 
cost,  therefore,  the  batch  box  system  is  superior  to  the  dump-body,  bulk-haulage 
system. 


TRUCK  CHASSIS  EQUIPPED  WITH  BATCH  BOX  FRAME 

Other  equipment  used  in  concrete  road  construction,  is  listed  in  the 
following  table  with  both  its  cost  and  weight.  The  prices  are  those  prevailing 
in  March,  1921.  The  equipment  as  listed  is  that  required  for  one  mixing  plant. 
The  derrick  at  the  transfer  point  would  not  be  needed,  of  course,  in  case  a com- 
plete railway  hauling  plant  is  used. 


70 


EQUIPMENT 

COST 

WEIGHT 

1 14-E  paver,  with  boom  and  bucket,  batch 

transfer,  l/2  caterpillar,  and  batch  meter 

$ 7,925.00 

25,400  lbs. 

1 finishing  machine 

1,800.00 

3,000  " 

1 subgrade  machine 

600.00 

2,300  " 

2000  feet,  6"  steel  form  @ $9.12  per  10  ft.  sec. 

1,824.00 

17,600  " 

1 double  unit  road  pump 

1,500.00 

4,000  » 

1 3/4  yard  clam  shell  bucket 

700.00 

2,530  " 

1 derrick  at  transfer  point 

1,200.00 

At  the  material  yard,  traps  are  provided  in  the  roof  on  the  tunnel  or 
in  the  "bottom  of  the  bin  for  the  purpose  of  loading  hatch  boxes.  These  traps 
are  generally  spaced  every  oar  length,  or  approximately  8 feet  apart  in  the 
tunnel.  The  type  of  trap  manufactured  by  The  Lakewood  Engineering  Company  es- 
pecially for  handling  sand  and  stone,  weighs  94  pounds  and  costs  $23*50. 


Two  inch  diameter  wrought  iron  pipe  is  the  type  generally  employed  in 
the  water  supply  system  for  a 14-E  or  21-E  mixer  plant.  For  a 28-E  mixer  a Z-l/z 
inch  pipe  should  be  used.  Pipe  smaller  than  2 inch  in  diameter  should  never  be 
used.  Two  inch  wrought  iron  pipe  weighs  3-2/3  pounds  per  foot  and  cost,  in 
March,  1921,  about  $0.30  per  foot. 


Union  should  be  provided  in  the  pipe  line  every  thousand  feet,  with 
gate  valves  every  quarter  or  half  mile.  Tees  should  be  provided  approximately 
80  feet  apart,  for  attaching  the  hose  leading  to  the  paving  mixer.  An  expansion 
joint  should  be  provided  every  half  mile  or  so  to  take  care  of  variations  in  the 
length  of  the  pipe  line.  This  is  a very  important  feature,  and  should  not  be 
overlooked.  The  C.  H.  & E.  Manufacturing  Company,  of  Milwaukee,  Wisconsin,  manu- 
facture an  eapansion  joint  which  is  quite  commonly  used,  though  most  contractors 
prefer  to  make  a home-made  affair  of  a piece  of  hose  or  a short  cross  pipe  3 or  4 
feet  long. 

Complete  illustrations  and  specifications  of  the  equipment  mentioned  in 
this  chapter  will  be  found  in  the  appendix. 


71 


CHAPTER  X. 

MATERIAL  UNLOADING-  AND  PROPORTIONING  YARD. 


Of  all  the  problems  confronting  the  highway  contractor,  the  problem  of 
receiving,  storing,  and  proportioning  material  is  the  most  important.  Some  of  the 
elements  of  this  problem,  notably  that  of  receiving  material,  is  largely  beyond 
the  contractor’s  control, and  is  dependent  upon  railroad  deliveries  which  are  fre- 
quently erratic  and  unreliable.  In  order  to  avoid  delay  from  this  source,  there- 
fore, the  prudent  contractor  provides  adequate  storage  facilities,  and  takes 
steps  to  insure  a proper  supply  of  material  during  the  construction  season  by 
storing  material  during  the  inactive  road  building  months. 

In  the  past  the  biggest  handicap  to  storing  raw  material  during  the 
inactive  season,  was  due  to  the  large  amount  of  working  capital  required.  At  the 
present  time,  however,  most  State  Highway  Departments  have  adopted  the  practice 
of  paying  monthly  estimates  on  material,  providing  it  is  stored  in  large  stock 
piles  near  a railroad.  As  a rule  no  payments  are  made  for  material  distributed 
along  the  road  in  windrows,  on  account  of  the  possibility  for  loss.  This  attitude 
of  State  Highway  Departments  affords  an  opportunity  to  practically  all  contractors 
to  prepare  themselves  properly  for  quantity  production  during  the  construction 
season,by  storing  materials  in  the  winter  months. 

Payments  on  cement  stored  during  the  winter  months  are  as  yet  not 
generally  made,  due  to  the  perishable  nature  of  the  product.  Some  states,  how- 
ever, notably  Pennsylvania,  permit  contractors  to  store  cement  after  the  fifteenth 
of  February,  and  make  monthly  payments  on  cement  so  stored.  This  reduoes  the 
amount  of  time  the  cement  is  kept  in  storage,  while  it  gives  the  contractor  about 
two  months  to  provide  a reserve  of  cement.  When  bagged  cement  is  used  no  payments 
are  made  for  the  bags,  and  the  contractor  is  compelled  to  invest  $>1.00  per  barrel 
in  this  non-productive  item.  Bulk  cement  possesses  a big  advantage  in  this  res- 
pect, inasmuch  as  no  money  is  tied  up  in  bags. 

Contractors  are  rather  wary  of  storing  cement  for  any  considerable 
length  of  time,  due  to  the  danger  of  spoiling.  Experience  in  the  past  justifies 
caution  on  their  part.  The  storage  of  cement  so  as  to  prevent  spoiling,  however, 
is  now  better  understood  than  it  was  in  the  past.  If  the  cement  house  is  so 
constructed  as  to  keep  out  moisture,  using  tar  paper  on  the  walls  and  floor  and 
storing  cement  so  as  to  prevent  the  circulation  of  air,  there  is  but  little  danger 
of  spoiling.  The  great  enen^  of  cement  is  moisture,  and  inasmuch  as  air  carries 
moisture  every  precaution  should  be  taken  to  prevent  its  circulation.  Cement 
should  be  piled  so  as  to  prevent  the  circulation  of  air  thru  it,  and  should  be 
covered  with  building  paper  or  canvas. 

Due  to  the  difficulty  of  securing  an  adequate  supply  of  material  during 
the  past  two  years,  some  contractors,  especially  those  who  were  formerly  engaged 
in  railroad  construction,  have  purchased  and  operated  their  own  standard  railroad 
equipment.  This  equipment  was  operated  between  the  points  of  material  supply  and 
the  job, in  the  exclusive  service  of  the  contractor  owning  it.  In  order  to  prevent 
loss  of  this  equipment,  or  divert  ion  at  a junction  point,  a man  or  two  was  gener- 
ally assigned  to  the  task  of  keeping  track  of  it.  The  railroad  charged  a certain 
amount  for  hauling  material  in  this  maimer,  and  reimbursed  the  contractor  for  the 
use  of  his  equipment  at  the  rate  of  about  $0,006  per  mile. 


<♦ 


* 


72 


A notable  example  of  the  use  of  privately  owned  standard  railroad  equip- 
ment in  highway  construction,  was  afforded  by  the  Crittenden-Ozark  road  project  in 
Arkansas  in  1920.  The  equipment  consisted  of  105  Western  air  dump  cars  of  30 
cubic  yard  capacity,  which  was  operated  from  the  gravel  pit  at  Wittenberg,  Missouri 
over  the  Frisco  Railroad  a distance  of  170  miles  to  the  job*  At  the  unloading 
point  material  was  dumped  on  each  side  of  the  track,  which  was  jacked  up  from  time 
to  time  so  as  to  form  a large  embankment  of  gravel.  This  embankment  at  one  un- 
loading point  was  800  feet  long  and  from  20  to  30  feet  high  at  the  highest  point. 
The  track  was  shifted  and  material  unloaded  by  a gang  of  14  men  and  1 foreman, 
at  a contract  price  of  $0.20  per  ton.  Previous  to  adopting  the  embankment  system, 
an  Erie  crane  equipped  with  a 3/4  yard  clam  shell  bucket  was  used  for  unloading 
material  at  a cost  of  $0.30  per  ton.  The  saving  in  the  cost  of  unloading  the 
287,400  tons  of  gravel,  was  thus  considerable.  The  loaded  oars  were  run  in  solid 
trains  of  30  cars,  each  containing  about  37  tons  of  material.  The  railroad 
charged  $50*00  per  loaded  car  for  hauling,  and  returned  the  empty  cars  free  of 
charge  in  mixed  trains.  The  road  district  received  the  rental  of  $0,006  per  mile 
from  the  railroad  for  the  use  of  their  equipment.  Loaded  trains  left  the  gravel 
pit  at  Wittenberg  at  6 o'clock  in  the  evening,  and  arrived  at  Chaffee,  a junction 
point  30  miles  from  Wittenberg, at  midnight.  At  9 or  10  o'clock  the  following 
morning,  the  loaded  train  was  at  the  job.  The  work  of  switching  and  dumping  the 
train  of  30  cars  required  about  2 hours.  The  round  trip  of  170  miles,  including 
switching,  dumping,  and  loading,  required  3 days.  During  the  last  week  of  November 
1920,  217  cars  were  unloaded.  The  Morgan  Engineering  Company,  of  Memphis,  Tenn. 
were  in  charge  of  this  project,  while  the  Industrial  Track  Construction  Company,  of 
St.  Louis,  Missouri  shifted  the  track  and  dumped  the  cars  for  a contract  price  of 
$0.20  per  ton.  The  cost  of  the  air  dump  cars  was  somewhat  over  $300,000,  and  it 
is  questionable  whether  the  saving  effected  by  this  system  is  sufficient  to  com- 
pensate for  the  loss  when  these  cars  are  sold  as  second  hand.  If  this  method  had 
not  been  adopted,  however,  all  work  in  this  road  district  would  have  been  suspended 
due  to  the  inability  to  secure  materials. 

The  question  of  whether  a contractor  is  justified  in  purchasing  standard 
railroad  equipment,  is  one  which  demands  careful  study.  If  such  equipment  can  be 
operated  long  enough  to  take  advantage  of  its  low  rate  of  depreciation,  not  ex- 
ceeding 10  per  cent  per  year,  privately  owned  standard  railroad  equipmait  will 
probably  prove  economical.  Even  though  the  actual  cost  of  hauling  on  some  par- 
ticular job  is  increased  due  to  privately  owned  railroad  equipment,  a contractor 
might  be  justified  in  purchasing  such  equipment  because  of  the  greater  reliability 
of  material  supply.  It  is  the  cost  of  such  intangible  factors  as  uncertainty  of 
material  supply,  which  ruin  contractors  more  often  than  the  increased  cost  of  some 
definite  operation  such  as  unloading  or  hauling  material.  Men  who  have  had  exper- 
ience in  Europe  claim  that  it  is  quite  the  common  thing  there  for  a contractor  to 
own  his  own  railroad  equipment.  Probably  as  road  work  is  organized  on  a greater 
scale  and  large  road  building  organizations  are  formed,  the  practice  of  owning 
standard  railroad  equipment  will  come  into  more  general  use.  Particularly  is  this 
true  of  railroad  contractors  who  enter  the  highway  construction  field,  inasmuch  as 
they  generally  possess  standard  gauge,  large  capacity,  earth  moving  equipment 
which  can  be  adapted  to  hauling  material  for  highway  construction. 

When  road  building  material  is  stored  in  quantity  at  unloading  points, 
the  problem  is  to  store  the  maximum  amount  of  material  on  the  minimum  amount  of 
space,  which  is  frequently  limited,  and  to  rehandle  the  material  most  economically. 
The  problem  of  rehandling  material  is  a very  important  one,  and  is  one  to  which 
many  contractors  do  not  give  proper  consideration.  The  rehandling  of  material  is 
often  very  troublesome  and  expensive,  and  close  attention  should  be  paid  to  this 
problem. 


* 


* 


73 


The  method,  of  storing  material  over  a tunnel  constructed  of  wood  frames 
and  sheeting  has  come  into  quite  general  use  during  the  past  two  years,  and  is 
recognized  as  one  of  the  best  on  account  of  the  ease  and  economy  with  which  mater- 
ials are  rehandled.  Traps  are  plaoed  in  the  roof  of  the  tunnel  approximately  8 • 
feet  apart,  or  every  car  length,  thru  which  material  can  he  charged  into  light 
railway  cars.  Due  to  the  large  amount  of  head  room  required,  the  tunnel  system 
is  impractical  for  loading  any  other  type  of  haulage  equipment  than  light  railway. 
The  tunnel  system  of  storage  provides  the  maximum  amount  of  storage  per  unit  of 
area  occupied.  A considerable  proportion  of  the  mterial  piled  over  a tunnel  will 
flow  thru  the  trap  by  gravity,  and  continuous  operation  of  the  concrete  mixing 
plant  is  thus  assured  in  spite  of  temporary  breakdowns  of  the  unloading  equipment. 
This  is  one  of  the  biggest  advantages  of  the  tunnel  system  of  storage.  Continuous 
operation  of  the  concrete  mixing  plant  is  also  insured  in  spite  of  temporary 
delay  in  railroad  shipments. 


PGR  TAT.  VIEW  OF  MATERIAL  TUNREL 


SIDE  VIEW  OF  MATERIAL  TUNNEL 


74. 


Material  storage  tunnels  can  tie  classed  under  three  general  heads, 
namely,  the  tunnel  entirely  above  ground,  the  tunnel  entirely  below  ground,  and 
the  tunnel  half  below  and  half  above.  These  three  general  methods  are  shown 
in  the  sketch  below. 


<r>7/V  Af  7-CS/V/V&A.  7~0  =7*/y'  =/<$/-?  T zi/*0  30  -O " 


A material  yard  must  sometimes  be  placed  on  a piece  of  rented  ground 
where  it  is  undesirable  to  excavate  a trench  for  the  tunnel,  or  the  presence  of 
rock  or  ground  water  may  prevent  sinking  the  tunnel.  In  such  a case  the  tunnel 
must  be  placed  above  ground,  as  shown  in  case  #1  above.  Assuming  a slope  of 
1 to  1 far  the  material,  25  per  cent  of  the  material  will  flow  by  gravity  as 
shown  by  the  dotted  line.  It  is  necessary  to  rehandle  the  remainder,  and  this 
must  generally  be  done  by  means  of  a crane  and  a clam  shell  bucket.  The  problem 
of  rehandling  should  be  eliminated  if  possible,  by  adopting  one  of  the  other 
methods  shown. 

Case  #2  shows  a tunnel  entirely  below  ground.  Assuming  slopes  of  1 to 
1 for  the  material,  50  per  cent  will  flow  by  gravity  as  shown  by  the  dotted  line. 
The  remainder  of  the  material  can  easily  be  rehandled  by  dragging  it  over  the 
tunnel  by  means  of  teams  and  scrapers,  or  by  means  of  a small  gasolene  engine  and 
a power  scraper.  From  the  standpoint  of  rehandling,  the  tunnel  entirely  below 
ground  is  to  be  preferred.  It  is  also  obvious  that  a smaller  amount  of  material 
must  be  rehandled  when  the  tunnel  is  placed  below  ground,  than  with  either  of  the 
other  methods.  It  is  possible,  therefore,  to  operate  for  a greater  length  of 
time  in  case  of  a breakdown  of  the  unloading  equipment,  than  with  either  of  the 
other  methods.  Many  contractors  prefer  placing  the  tunnel  entirely  below  ground 
even  though  the  cost  of  so  doing  is  considerably  greater  than  that  of  the  other 
two  methods,  and  even  though  a pump  must  be  installed  far  handling  ground  water. 

Case  #3,  with  the  tunnel  partly  below  and  partly  above  ground,  is  a 
method  which  is  most  generally  used.  In  this  method  the  material  excavated  from 
the  trench  is  banked  against  the  side  of  the  tunnel,  as  shown  by  the  cross-hatch- 
ing, so  as  to  make  the  problem  of  refilling  the  trench  an  easy  one.  With  a tunnel 
of  this  kind,  37  per  cent  of  the  material  will  flow  by  gravity.  Due  to  the 
sloping  earth  banked  the  outside,  the  problem  of  rehandling  material  is  practi- 
cally no  more  difficult  than  where  the  tunnel  is  placed  entirely  below  ground. 

The  quantity  of  material  which  can  be  stored  by  the  tunnel  method  de- 
pends upon  the  length  of  the  tunnel  and  upon  the  height  to  which  material  can  be 
piled.  The  height  to  which  material  can  be  piled  depends,  in  turn,  upon  the 
length  of  boom  of  the  unloading  crane  or  derrick.  Data  sheets  showing  the  detail 
of  design  of  tunnels  and  their  storage  capacity,  will  be  found  in  the  appendix. 


75 


The  cost  of  a material  storage  tunnel  depends,  of  course,  upon  the  cost 
of  lumber  and  the  cost  of  labor*  Tunnels  have  been  constructed  of  old  railroad 
ties  and  of  timber  cut  down  by  the  contractor  in  clearing  the  right  of  way*  Such 
tunnels  were  very  moderate  in  cost*  As  a rule,  where  dimensioned  lumber  is  used 
at  a cost  of  about  $60.00  per  thousand  feet  board  measure  and  carpenter  labor  cost 
about  $1.00  per  hour,  a tunnel  build  according  to  the  design  in  the  appendix,  will 
cost  about  $10*00  per  lineal  foot  in  place.  This  is  exclusive  of  the  cost  of 
grading,  and  is  based  upon  a cost  of  about  $25.00  to  $30*00  per  thousand  feet 
board  measure  for  fabricating.  As  shown  by  the  design,  the  tunnel  is  so  construct- 
ed that  it  can  be  knocked  down  and  moved  from  one  job  to  another.  The  use  of 
structural  steel  frames  in  a tunnel  has  been  proposed  and  has  been  given  consider- 
able thought,  but  to  date  wood  has  been  exclusively  used  in  building  tunnels  ex- 
cept in  one  case  where  steel  "I"  beams  supported  the  roof.  Tunnel  traps  costing 
$23*50  each  in  March,  1921,  must  be  placed  in  the  roof  of  the  tunnel  every  8 feet* 
The  final  cost  of  the  tunnel,  therefore,  is  about  $13.00  per  foot. 

Where  a large  amount  of  material  is  to  be  stored  during  the  inactive 
road  building  months,  the  tunnel  system  becomes  very  expensive.  Due  to  the  limit- 
ed reach  of  the  boom  on  the  unloading  crane,  it  is  necessary  to  place  material  in 
a long  pile.  A concrete  road  18  feet  wide,  of  a 1-2-3  mixture,  and  7-1/3  inches 
average  thickness,  requires  1,120  cubic  yards  of  sand  and  1,680  cubic  yards  of 
stone  per  mile,  or  a total  of  2,800  cubic  yards  of  material*  A crane  with  a 45 
foot  boom  equipped  with  a 3/4  cubic  yard  clam  shell  bucket,  can  pile  material 
to  a height  of  about  20  feet.  Assuming  a 1 to  1 slope  for  the  material,  such  a 
pile  will  contain  about  15  cubic  yards  per  lineal  foot.  A pile  187  feet  long  is, 
therefore,  required  to  store  sufficient  material  for  1 mile  of  road,  while  a pile 
750  feet  long  is  required  to  store  material  for  4 miles  of  road.  Obviously  a 
tunnel,  at  $13.00  per  lineal  foot,  would  be  very  expensive  in  this  case* 


LONG  MATERIAL  STORAGE  PILE 


In  order  to  eliminate  the  expense  of  placing  a tunnel  thruout  the  en- 
tire length  of  a long  pile  of  material,  the  use  of  short  cross  tunnels  has  been 
suggested.  These  tunnels  would  be  placed  crosswise  of  the  material  pile  as  shown 
in  the  following  sketch.  A small  percentage  of  material  would  flow  by  gravity, 
and  the  remainder  could  be  rehandled  by  means  of  a light  drag  line,  or  preferably 
by  means  of  a hoisting  engine  and  a line  attached  to  a scraper. 


76. 


-300  - o ' 


r 


00X0 


0SO-O 

R 


- 

r~> 

, — 7 TV  A**/ 

> 

i 

1 ‘ 
• 

*L 


l ; i 



00/01X07' 

3 

TT 


y- 


£T  sr  > 

i*'/~r/f  / -ro  / 


R?  - & 


S£’C7’/<?'V  c -& 


Another  method,  of  rehandling  material  where  it  is  stored  in  a long 
pile  is  "by  means  of  small  movable  bins  operating  on  tracks  the  entire  length  of 
the  pile*  This  method  is  illustrated  by  means  of  the  following  sketch  and  photo- 
graph. 


/ // 

‘*rmJi3  ~ O .....  »• 

t ^ 

r - 

*30/007  0/Xj0 

*07-0/0/3  0/0.  /£ 

) 

\ ) 

- o/<o/i7~  00/0x07-  /~0/o 
337-txSOX  00 //-S  00  3/sy 
T00O0y  ix*3/v  000X0  7-  0t  07/0700 
0X0  0000030  .0  3/00/.  0730 


K__ 


00/oO  &/sO. 


-*v 


a//o  7-00OX 
S-O  " &0O<$3 


•SToxf  0/x 


' 


• c 


■ ■».  \ 

: -v 


• .0  *.  „ 


MOVABIE  BIN  REHANDLING  PLANT 

The  movable  bin  illustrated  above,  operates  on  a track  of  about  8 foot 
gauge.  Material  can  be  loaded  into  the  bin  by  means  of  a crane  and  clam  shell 


77 


■bucket,  as  shown  in  the  photograph,  a bucket  elevator  and  a power  scraper,  or  a 
portable  bucket  loader  such  as  that  illustrated  on  page  5,  The  crane  in  the 
photograph  shown  above  is  an  Erie  steam  shovel  equipped  with  a 30  foot  boom. 

Strips  of  steel  bolted  on  the  wheels  form  flanges. 

When  movable  bins  are  used  they  are  sometimes  placed  on  a flat  car,  the 
sand  bin  on  one  car  and  the  stone  bin  on  the  other.  The  locomotive  crane  is 
placed  between  the  cars  and  operates  back  and  forth  along  the  material  pile.  With 
a system  of  this  kind  it  is  necessary  to  lay  the  light  railway  track  to  one  side 
of  the  bin  track,  and  to  charge  the  batch  boxes  by  means  of  side  gates  in  the  bin. 
Another  method  consists  of  operating  the  crane  between  bins,  which  occupy  more  or 
less  of  a fixed  position.  Where  the  material  pile  is  long,  however,  one  crane 
might  not  suffice  for  this  purpose.  If  power  scrapers  are  used,  a small  gasolene 
engine  can  be  mounted  beneath  each  bin  for  the  purpose  of  dragging  material  up 
to  tire  bucket  elevator.  This  engine  can  also  be  used  for  moving  the  bins,  by 
means  of  a line  attached  to  a "dead  man'*.  Teams  and  drag  scrapers  might  be  used 
for  dragging  material  to  the  bucket  elevator,  but  this  method  is  more  expensive 
than  the  power  scraper  method.  When  the  bucket  elevator  and  power  scraper  method 
is  used,  it  is  possible  to  lay  the  ligit  railway  between  the  rails  of  the  bin 
track  and  operate  the  batch  box  cars  underneath  the  bin.  The  photograph  below 
illustrates  this  method. 


LIGHT  RAILWAY  TRACK  IN  CENTER  OP  MOVABLE  BIN  TRACK 


Instead  of  using  movable  bins,  two  or  more  small  stationary  bins  are 
sometimes  used.  In  this  case  the  locomotive  crane  operates  between  the  material 
pile  and  the  bin.  Obviously  with  this  system  it  is  not  feasible  to  store  material 
in  a very  long  pile.  The  movable  bin  method  is  to  be  preferred  to  the  stationary 
bin  method. 

The  movable  bin  method  of  rehandling  material  is  quite  commonly  used 
where  material  is  to  be  stored  in  large  quantities.  With  this  method  it  is 
possible  to  release  the  unloading  crane  for  duty  at  some  other  unloading  point, 
as  soon  as  sufficient  material  has  been  stored  at  the  point  in  question.  The 
movable  bin  method  is  perhaps  the  best  method  of  rehandling  large  quantities  of 
material. 


78 


SMALL  STATIONARY  BIN  REHANDLING  PLANT 


In  hilly  country,  it  is  frequently  possible  to  build  a trestle  thru 
which  material  can  be  dumped  from  bottom  dump  cars  onto  a pile  or  tunnel  below* 
This  method  of  operation  requires  bottom  dump  cars,  which  might  be  difficult  to 
secure  in  certain  parts  of  the  country.  If  it  is  necessary  to  construct  any 
considerable  amount  of  trestle,  this  method  might  become  quite  expensive.  The 
cost  of  building  the  trestle,  however,  would  be  offset  somewhat  by  the  decreased 
cost  of  unloading  and  by  the  elimination  of  an  unloading  crane.  Whether  these 
factors  are  sufficient  to  justify  the  use  of  the  trestle  method  depends  upon 
local  conditions. 


SMALL  MATERIAL  DUMPING  TRESTLE 

In  level  country  a material  dumping  trestle  might  be  used  when  bottom 
dump  cars  are  available,  but  the  cost  in  such  a locality  would  probably  be  greater 
than  in  hilly  country.  The  trestle  method  of  unloading  material  has  been  used  in 
level  country,where  the  size  of  the  job  was  sufficient  to  warrant  the  investment* 


79 


A notable  example  of  the  use  of  a trestle  for  unloading  purposes  in  level  country, 
is  that  of  Twohy  Brothers,  of  Portland,  Oregon,  on  their  288  mile  concrete  road 
contract  in  Maricopa  County,  Arizona.  This  trestle,  illustrated  in  the  photographs 
"below,  was  "built  according  to  the  standards  of  the  Southern  Pacific  Railroad,  with 
proper  modification  to  permit  a bunker  to  be  suspended  underneath.  The  approach 
is  on  a 4 per  cent  grade,  and  a light  railway  track  runs  underneath  the  trestle* 
This  trestle  has  a storage  capacity  of  about  2,500  cubic  yards  of  material,  and 
cost  $20,000.  It  can  be  dismantled,  and  set  up  in  another  location* 


TRESTLE  SYSTEM  OP  UNLOADING  MATERIAL 


A material  trestle,  such  as  that  illustrated  above,  is  obviously  too 
expensive  for  anything  but  a large  job.  Unloading  equipment  is  entirely  eliminat- 
ed, however.  Material, once  placed  in  the  bunker,  is  loaded  into  light  railway 
cars  by  means  of  gravity,  so  the  problem  of  rehandling  need  not  be  considered. 

One  of  the  most  common  methods  of  storing  and  rehandling  material,  is 
the  stock  pile  and  bin  n»thod.  A derrick  is  generally  used  for  unloading  material 
which  is  placed  in  large  piles  near  the  bin.  The  objection  to  this  method  is  the 


80 


restricted  amount  of  storage  possible,  on  account  of  the  limited  reach  of  the  boom 
of  the  derrick  or  crane.  A derrick  with  a 60  foot  boom  and  a 3/4  yard  clam  shell 
bucket,  can  pile  material  to  a height  of  about  30  feet.  Such  a pile,  which  is 
generally  conical  with  a 1 to  1 slope,  will  contain  about  1,000  cubic  yards  of 
material,  and  two  such  piles  are  all  that  one  derrick  can  reach.  The  quantity  of 
material  stored,  therefore,  is  not  sufficient  to  construct  one  mile  of  18  foot 
concrete  road. 


STOCK  PIES  AND  BIN  METHOD  OF  HANDLING  MATERIAL 


Another  objection  to  the  method  described  above,  is  due  to  the  in- 
ability of  the  derrick  to  reach  the  material  at  the  far  side  of  the  pile.  It  is 
generally  necessary,  therefore,  to  use  a line  from  the  hoisting  engine  to  a power 
scraper, for  the  purpose  of  dragging  the  material  to  the  point  where  the  derrick 
can  reach  it.  On  account  of  the  limited  storage  capacity  of  the  bins  generally 
employed  with  this  type  of  unloading  plant,  a breakdown  of  the  derrick  would 
cause  a shut  down  of  the  concrete  mixer.  To  provide  for  only  one  day's  operation 
of  a 14-E  mixing  plant,  will  require  a bin  of  about  200  cubic  yards  capacity.  A 
large  bin,  such  as  that  illustrated  in  the  photograph  on  the  following  page,  is 
very  expensive.  Rather  than  use  a bin,  it  would  seem  to  be  preferable  to  place  a 
short  tunnel  underneath  the  pile  of  material,  as  illustrated  on  the  next  page. 

The  type  of  derrick  most  commonly  used  is  the  stiff  leg  type,  though, 
where  conditions  permit,  guy  derricks  are  often  used.  Derricks  are  generally 
fixed  in  position  and  can  unload  from  but  one  car  at  a time,  so  it  is  necessary 
to"spot"  each  individual  car.  Traveling  derricks  are  sometimes  used,  but  these 
outfits  are  very  cumbersome  and  almost  as  expensive  as  a crane.  A derrick  of  any 
type  is  much  more  cumbersome  and  slow  than  is  a crane,  but  \diere  a contractor  al- 
ready possesses  derrick  equipment  it  is  probably  more  economical  for  him  to  use 

it,  at  least  temporarily,  than  it  is  to  purchase  a crane.  When  a derrick  is 

used  for  unloading  purposes  it  is  desirable  that  the  boom  be  at  least  60  feet 

long.  A long  boom  is  also  desirable  on  a crane,  for  the  longer  the  boom  the 

greater  the  amount  of  material  that  can  be  stared. 


81 


LARGE  MATERIAL  STORAGE  BUT 


TUNKELS  BEHEATH  PILES  STORED  BY  DERRICK 

When  a combined,  light  railway  and.  motor  truck:  haulage  plant  is  vised,  it 
is  impractical  to  build  a tunnel  large  enough-  to  permit  the  trucks  to  pass  thru* 
Bins  are  generally  used  with  this  type  of  plant,  but  the  tunnel  system  of  storage 
can  be  employed  by  operating  platform  cars  thru  the  tunnel  on  a short  stretch  of 
track.  Each  car  will  carry  4 batch  boxes,  and  these  batch  boxes  will  be  trans- 
ferred to  motor  trucks  at  the  entrance  to  the  tunnel*  The  cars  can  be  pushed  thru 
the  tunnel  by  hand  by  two  men  if  there  are  no  grades,  or  a small  hoisting  engine 
can  be  used  for  this  purpose.  A light  derrick  can  be  placed  on  the  transfer  plat- 
form, for  transferring  batch  boxes  from  car  to  platform  to  truck.  Another  method 
of  transferring  batch  boxes,consists  of  carrying  all  4 boxes  on  a frame.  This 
frame  is  equipped  with  wheels,  so  that  it  can  be  rolled  from  the  car  to  the  plat- 
form to  the  truck.  In  order  to  place  the  truck  body  on  the  same  level  with  the 
platform,  it  is  generally  necessary  to  excavate  a pit  into  -which  the  trucks  can 
run.  A small  hand  winch  and  a light  line,  will  furnish  power  for  moving  these 


82 


frames.  With  this  plan  of  operation  it  is  necessary  to  have  a frame  for  each 
truck,  a frame  for  each  of  the  two  platform  cars,  and  several  extra  frames  to  per- 
mit the  storage  of  loaded  frames  on  the  platform.  A shuttle  system  of  two  plat- 
form cars  carrying  4 hatch  boxes  each, operated  by  4 men,  is  sufficient  to  supply 
batch  boxes  to  the  transfer  platform  at  the  rate  of  30  per  hour  when  the  length 
of  the  tunnel  does  not  exceed  300  feet.  The  layout  of  a plant  such  as  that  just 
described,  is  shown  in  the  sketch  below. 


The  material  unloading  device  commonly  employed  on  small  jobs,  consists 
of  a portable  bin  equipped  with  an  elevating  skip  or  a bucket  elevator.  Such  a 
bin  has  a capacity  of  about  50  tons  of  material  at  the  most,  and  its  successful 
operation  depends  upon  day  to  day  delivery  of  material  by  the  railroad.  Inasmuch 
as  no  storage  is  provided,  the  lack  of  insurance  against  delay  due  to  erratic 
railroad  delivery  is  obvious.  A bin  of  this  type  of  50  ton  capacity  costs  about 
$1,800.00.  The  Gal  ion  Iron  Works,  of  Gal  ion,  Ohio,  and  the  Sunbury  Manufacturing 
Company,  of  Sunbury,  Ohio,  manufacture  typical  bins  of  this  class. 


THE  SUUBURY  IMLOADER 


The  bucket  elevator  system  of  unloading  material  is  sometimes  used  in 
conjunction  with  bins  of  considerable  capacity,  say  50  to  75  cubic  yards.  With 
this  system  of  unloading^ it  is  necessary  to  "spot"  each  car  accurately  over  the 
pit  which  it  is  necessary  to  excavate  beneath  the  railroad  track.  From  this  pit 
material  is  fed  to  the  bucket  elevator  by  means  of  a gate.  The  bucket  elevator 
system  provides  no  storage  capacity  outside  of  that  in  the  bin  itself.  A bin  of 
this  size,  illustrated  in  tie  following  photograph,  is  quite  expensive.  This 
system  of  unloading  is  not  recommended  for  any  but  very  small  jobs. 


BIN  AND  BUCKET  ELEVATOR  SYSTEM 

The  most  common  method  of  handling  cement  at  the  present  time  is  the 
hag  method,  each  hag  containing  94  pounds  or  about  1 cubic  foot  of  cement.  Bagged 
cement  is  generally  stored  in  a shed,  and  the  hags  are  either  emptied  dir.ectly 
into  the  cement  compartments  of  the  hatch  boxes  or  into  small  hoppers.  These 
hoppers  contain  sufficient  cement  for  one  hatch.  When  light  rail-way  haulage  is 
used  a long  platform  is  generally  provided  alongside  the  cement  storage  shed. 

The  train  passes  alongside  this  platform,  or  underneath,  and  takes  on  the  proper 
amount  of  cement  from  each  hopper.  The  photograph  on  page  75  shows  the  cement 
platform  along  the  cemait  house,  which  is  placed  at  one  end  of  the  material  tunnel. 

Bagged  cement  is  generally  unloaded  from  cars  into  the  cement  shed  or 
onto  the  cement  platform  by  hand,  though  sometimes  belt  conveyors  are  used.  The 
cement  platform  is  generally  placed  at  the  same  height  as  the  car  floor,  so  that 
hand  trucks  can  he  used  for  handling  cement.  The  photograph  below  illustrates 
the  method  of  handling  bagged  cement  by  means  of  hand  trucks.  The  men  in  the  fore- 
ground are  engaged  in  dumping  cement  into  small  hoppers,  which  discharge  into  the 
light  railway  cars  operating  beneath  the  platform. 


METHOD  OF  HANDLING  BAGGED  CEMENT 


84 


The  principal  objection  to  placing  cement  in  bags,  is  the  added  invest- 
ment of  $1.00  per  barrel  required  by  the  cement  companies  for  the  bags.  Of  course, 
this  money  is  refunded  when  the  sacks  are  returned,  but  meanwhile  a considerable 
amount  of  working  capital  has  been  invested  in  a non-productive  item.  Many  bags 
are  lost  or  tarn  or  are  wet,  so  that  the  contractor  receives  no  credit  for  them 
from  the  cement  company.  Experience  indicates  that  the  average  cement  bag  is  good 
for  about  8 trips,  so  that  a contractor  should  figure  on  ultimately  paying  for  1 
bag  out  of  every  8.  He  might,  perchance,  have  the  good  fortune  to  receive  all 
good  bags  fljr  a while,  but  if  he  stays  in  business  for  more  than  a year  or  two  he 
will  surely  receive  his  proportionate  share  of  worn  out  bags.  The  cost  of  unload- 
ing and  handling  bagged  cement  is  somewhat  greater  than  that  of  bulk  cement,  while 
the  price  charged  by  the  cement  companies  is  $0.05  per  barrel  greater  than  for 
bulk  cement.  During  the  past  two  years  the  practice  of  using  bulk  cement  has  be- 
come quite  general. 

ihen  bulk  cement  was  first  used  in  highway  construction,  in  1914,  it 
was  shipped  in  box  cars,  and  was  unloaded  by  means  of  wheeled  scoops  directly 
into  w’agons.  The  cement  was  hauled  in  these  wagons  and  unloaded  into  weather 
tight  boxes, spaced  at  intervals  along  the  road,  by  means  of  scoop  shovels  and 
coal  shutes.  From  these  boxes  the  cement  was  shoveled  into  wheelbarrows,  and 
handled  in  the  same  manner  as  sand  and  stone. 

At  the  present  time  bulk  cement  is  frequently  shipped  in  open  top  cars, 
and  is  protected  from  the  weather  by  means  of  a tarpaulin  supported  on  light 
wooden  frames.  The  cement  company  charges  for  this  tarpaulin  in  the  same  manner 
as  for  cement  bags,  and  reimburses  the  contractor  when  the  tarpaulin  is  returned. 
Several  instances  are  known  where  the  tarpaulin  was  removed  by  someone,  and  the 
cement  exposed  to  the  elements.  One  such  car  after  passing  thru  three  heavy 
rains  was  found  to  contain  a 6 inch  crust,  beneath  which  the  cement  was  perfectly 
good.  The  cement  was  so  well  protected  by  this  crust,  that  it  was  even  proposed 
to  do  away  with  tarpaulins  altogether  and  to  sprinkle  the  cement  in  order  to  form 
a crust. 

When  bulk  cement  is  shipped  in  open  top  cars  it  can  be  unloaded  by 


means  of  a clam  shell  bucket  in  the  same  manner  as  sand  and  stone,  and  placed  in 
a bin  thru  hatches  in  the  roof.  Cement  is  loaded  into  the  light  railway  train 
in  the  same  manner  as  sand  and  stone. 


85 


Bulk  cement  shipped  in  box  cars  is  handled  by  a number  of  methods.  One 
method  is  to  construct  a large  box  or  bin  at  the  car  door,  of  sufficient  capacity 
to  hold  one  or  more  cars  of  cement.  The  cement  can  be  unloaded  into  this  bin  by 
means  of  a power  scraper  or  wheeled  scoops.  During  the  noon  hour  or  at  the  end 
of  the  day,  the  crane  can  transfer  the  cement  from  the  temporary  bin  into  the 
permanent  bin  by  means  of  a clam  shell  bucket.  Another  method  of  unloading  cement 
in  bulk  from  box  cars,  is  by  means  of  a portable  belt  conveyor  such  as  that 
manufactured  by  the  Barber-Green  Company,  of  Aurora,  Illinois.  One  end  of  this 
conveyor  is  placed  on  top  of  the  bin  so  as  to  discharge  into  a hatch,  and  the 
other  in  the  box  car.  Cement  is  shoveled  onto  the  conveyor  by  means  of  scoop 
shovels.  In  order  to  prevent  the  blowing  away  of  cement,  it  is  wise  to  surround 
the  belt  conveyor  with  a canvas  covering  supported  on  a light  wooden  frame.  The 
best  method  of  unloading  bulk  cement  from  box  cars,  is  by  means  of  a power 
scraper  such  as  that  used  in  unloading  grain.  The  cement  is  scraped  into  a 
hopper  at  the  door  of  the  car,  from  which  it  is  fed  to  a bucket  elevator  which 
carries  it  into  a bin. 

A particular  job  comes  to  mind  at  this  time,  on  which  bulk  cement  was 
received  in  box  cars  at  a railroad  siding  6 miles  from  the  job.  The  cement  was 
unloaded  into  a thousand  barrel  bin  at  the  railroad  siding  by  means  of  the  power 
scraper  and  bucket  elevator  system.  Motor  trucks  carried  the  cement  from  the  bin 
at  the  railroad  siding  up  an  incline  to  a bin  near  the  job.  The  trucks  dumped 
the  cement  into  a hopper,  from  viiieh  it  was  fed  to  a bucket  elevator  and  placed 
in  a 2,000  barrel  bin.  Light  railway  cars,  on  their  way  from  the  gravel  pit  to 
the  job,  passed  beneath  this  bin  and  took  on  the  proper  amount  of  cement.  The 
photograph  below  shows  this  method  of  handling  bulk  cement. 


HANDLING  BULK  CEMSTTT  BY  MOTOR  TRUCK 


Cement  companies  claim  that  bulk  cement  will  effect  a saving  of  $0.25 
per  barrel  over  bagged  cement.  When  proper  charges  are  made  for  handling  equip- 
ment, bins,  etc*  it  is  not  believed  that  the  net  saving  will  exceed  $0.15  per 
barrel.  This  saving,  hoirever,  is  sufficient  to  warrant  a contractor  giving 
serious  consideration  to  the  use  of  bulk  cement.  During  the  car  shortage  pre- 
vailing the  past  two  years,  it  was  generally  much  easier  to  secure  shipments  of 
bulk  cement  than  of  cement  in  bags. 


86 


The  trestle  system  of  unloading  material  is  well  adapted  to  the  handling 
of  hulk  cement,  for  it  would  seem  to  he  entirely  feasible  to  ship  hulk  cement  in 
bottom  dump  cars  and  dump  directly  into  the  hunker  underneath  the  trestle  thru 
hatches.  In  case  hulk  cement  is  shipped  in  box  cars,  a power  scraper  could  he 
used  to  scrape  the  cement  directly  into  the  hunker  thru  small  hoppers. 

Bul]f  cement  storage  bins  are  more  expensive  than  storage  sheds  for 
bagged  cement.  In  general  a hulk  cement  bin  will  cost  about  $400.00  to  $500.00 
per  car  of  capacity,  whereas  a good  cement  shed  will  not  cost  more  than  about  one- 
fourth  of  this  amount. 

Sometimes  it  is  desired  to  employ  a method  of  storing  material  which 
possesses  greater  capacity  than  the  ordinary  bin  method,  in  a location  where, for 
some  reason  or  other, it  is  not  desired  to  use  a tunnel.  In  such  a case  the  so- 
called  bunker  method  will  frequently  meet  the  requirements.  The  sketch  below 
illustrates  the  general  features  of  this  method. 


It  is  apparent  that  material  can  be  heaped  up  on  a bunker  after  it 
is  level  full,  so  as  to  obtain  almost  as  much  storage  capacity  as  a tunnel  placed 
above  ground.  Furthermore  material  need  not  be  rehandled,  when  once  placed  in  the 
bunker.  The  bunker  method  does  not  require  much  more  timber  than  the  tunnel 
method,  and,  considering  its  greater  storage  capacity,  it  requires  less  timber  thaj 
a bin.  It  is  highly  desirable  for  a contractor  to  store  the  largest  amoiint  of 
material  possible,  and  on  those  jobs  where  it  is  impractical  to  use  a tunnel  and  a 
storage  capacity  greater  than  that  afforded  by  bins  is  desired,  tie  bunker  method 
might  prove  suitable. 

In  laying  out  a material  yard,  it  is  desirable  that  bins  or  tunnels  be 
so  arranged  that  the  process  of  loading  is  a continuous  one  and  no  doubling  back 
is  required.  Cement  storage  sheds  or  bins  are,  therefore,  generally  placed  in 
direct  line  with  the  material  tunnel.  It  is  also  desirable  to  arrange  the  layout 
so  that  when  bagged  cement  is  used,  it  can  be  unloaded  directly  into  batch  boxes 
carried  on  railway  cars  or  trucks,  as  illustrated  on  page  65.  Such  an  arrangement 
largely  eliminates  the  cost  of  rehandling  cement  from  the  shed  to  the  batch  boxes. 
As  a rule  the  cost  of  unloading  bagged  cement  into  a shed  is  about  $0.10  per 
barrel,with  labor  at  about  $4.00  per  10  hour  day,  and  the  cost  of  rehandling  ce- 
ment to  the  batch  boxes  is  about  the  same.  When  the  material  yard  is  so  arranged 
as  to  permit  unloading  directly  into  batch  boxes,  the  saving  per  barrel  is 
approximately  $0.10.  The  method  of  direct  charging  of  batch  boxes  from  the  cement 
cars,  should  of  course  not  be  used  unless  plenty  of  track  room  is  available  or  if 
it  entails  excessive  demurrage  charges. 


87 


When  "bagged  cement  is  used  the  problem  of  measuring  the  cement  has  al- 
ready been  taken  care  of  by  the  cement  manufacturer,  for  each  94  pound  bag  is  al- 
most universally  accepted  as  containing  1 cubic  foot  of  cement.  When  bulk  cement 
is  used,  however,  a method  of  measuring  must  be  devised  by  the  contractor.  One 
cubic  foot  of  loose  cement  seldom  weighs  94  pounds,  on  account  of  the  "fluffing'* 
of  the  cement.  For  this  reason  most  engineers  now  require  that  bulk  cement  be 
measured  by  weight.  When  volumetric  measurement  of  bulk  cement  is  permitted,  an 
efficient  and  rapid  method  is  shown  in  the  photograph  below. 


VOLUMETRIC  METHOD  OF  MEASURING  BUIK  CEMENT 

Cement  is  measured  in  the  method  illustrated  above,  by  means  of  two 
sliding  gates  operating  on  the  same  lever  arm.  The  volume  of  the  measuring  shaft 

between  these  two  gates  is  just  sufficient  to  provide  cement  for  one  batch.  Some 

difficulty  was  experienced  at  first  in  cutting  the  stream  of  cement  at  the  upper 
gate,  thru  the  full  15  inch  cross  section  of  the  shaft.  The  difficulty  was 
eliminated  by  inserting  a small  hopper  arrangement  in  the  measuring  shaft  just 
above  the  upper  gate,  so  that  the  stream  of  cement  could  be  reduced  to  a 6 inch 
cross  section. 

When  bulk  cement  is  measured  by  weight,  one  cubic  foot  is  assumed  to 
weigh  94  pounds.  It  is  not  a difficult  matter  to  devise  a weighing  device  to 
measure  bulk  cement.  A number  of  devices  for  weighing  grain  are  on  the  market, 

but  these  are  generally  too  expensive  for  the  purpose  of  weighing  cement  and  they 

do  not  give  better  results  than  a home-made  device.  A bulk  cement  weighing  device 

I manufactured  by  The  Lakewood  Engineering  Company,  of  Cleveland,  Ohio,  for  use  on 
large  installations,  is  shown  in  the  photograph  on  the  following  page# 

In  order  to  prevent  dusting  when  charging  batch  boxes  with  bulk  cement, 
a canvas  tube  should  be  provided.  This  tube  leads  from  the  cement  measuring  de- 
vice, and  can  be  tucked  into  the  cement  compartment  of  a batch  box.  Not  only 
does  this  tube  prevent  dusting,  but  it  enables  a car  to  be  loaded  even  though  it 
is  not  accurately  spotted. 


■» 


BULK  CEMENT  WEIGHING  DEVICE 


A problem  with  which  a contractor  is  frequently  confronted,  is  that  of 
deciding  whether  to  utilize  existing  side  tracks  for  unloading  purposes  or  to  build, 
a private  siding.  Existing  sidings  frequently  are  not  located  advantageously  with 
respect  to  the  job,  and  they  must  often  be  shared  with  other  interests.  When  a 
contractor  builds  his  own  siding  he  is  generally  assured  of  exclusive  use  of  it, 
and  the  inconvenience  and  delay  resulting  from  the  joint  use  of  a siding  with  other 
interests  is  thus  avoided.  It  is  also  possible  for  him  to  so  locate  his  sidings, 
as  to  reduce  his  ton  mileage  very  considerably.  Whether  the  factors  of  decreased 
ton  mileage  due  to  proper  location  of  siding,  and  smaller  chance  of  delay  due  to 
a private  siding,  are  sufficient  to  warrant  the  cost  of  building  a private  siding, 
can  only  be  determined  after  proper  consideration  of  all  factors. 

When  light  railway  haulage  is  used  unloading  sidings  can  be  located  al- 
most anywhere,  because  light  railway  track  can  be  laid  thru  or  around  the  edge  of 
fields,  up  ravines,  around  the  side  of  hills,  etc.  In  other  words  with  light 
railway  haulage,  the  location  of  unloading  sidings  is  not  limited  by  existing  roads. 
This  enables  sidings  to  be  so  located  as  to  reduce  ton  mileage  to  a minimum.  With 
any  method  of  haulage  other  than  light  railway,  on  the  other  hand,  it  is  generally 
necessary  to  either  utilize  existing  sidings,  or  to  locate  new  ones  near  existing 
roads.  The  resulting  location  due  to  the  necessity  of  considering  existing  roads, 
might  be  such  that  the  reduction  in  ton  mileage  is  insufficient  to  compensate  for 
the  cost  of  the  siding.  A private  siding  is  always  desirable,  however,  and  fre- 
quently the  lessened  chances  of  delay  incident  to  the  use  of  a private  siding  will 
alone  justify  its  construction. 

Sometimes  a number  of  unloading  sidings  are  available.  The  problem  then 
is  to  determine  how  many  of  these  sidings  to  use.  By  using  all  of  them  the  ton 
mileage  and  the  amount  of  equipment  required  would  probably  be  reduced,  but  the  de- 
lay due  to  moving  from  one  location  to  another  might  be  very  serious.  Here  again, 
judgment  and  experience  must  be  exercised  in  deciding  upon  the  plan  of  operation. 

In  general  it  will  not  profit  a contractor  to  establish  so  many  unloading  points, 
that  the  delay  in  moving  from  one  to  the  other  will  leave  him  with  unfinished 
work  to  be  carried  over  to  the  following  year.  The  possibility  of  loss  due  to 
carrying  over  work  to  the  following  year,  is  frequently  so  great  as  to  justify  a 
considerable  increase  in  the  ton  mileage  due  to  using  fewer  unloading  points.  The 
proper  method  is  to  use  the  fewest  possible  unloading  points  consistent  with  a 
fairly  low  ton  mileage,  in  order  to  reduce  delay  due  to  moving  unloading  points 
to  a minimum.  The  general  method  of  procedure  in  deeding  upon  the  number  of  un- 
loading points  to  use,  is  to  compare  the  cost  of  installing  and  operating  the 


t 


r 


i* 


89. 


additional  unloading  point  with  the  saving  due  to  decreased  ton  mileage  and  the 
cost  of  delay  caused  by  moving. 

Many  contractors  consider  the  delay  of  two  weeks  to  one  month  in  dis- 
mantling a material  yard  at  one  point  and  installing  it  at  another,  to  be  so  ser- 
ious, coming  as  it  does  in  the  height  of  the  construction  season,  that  they  make 
every  effort  to  so  arrange  a job  as  not  to  require  moving  the  material  yard.  Some 
contractors  will  bid  only  on  such  jobs  as  can  be  handled  from  one  material  yard, 
and  only  on  such  jobs  as  they  can  finish  in  one  season.  If  they  bid  on  longer  jobs 
they  so  arrange  the  work  as  to  permit  the  unloading  point  to  be  moved  in  the  winter 
time. 

The  central  unloading  and  proportioning  yard  featured  in  modem  highway 
construction  not  only  lends  itself  readily  to  the  use  of  bulk  cement  and  to 
economy  in  bags  in  case  of  bagged  cement,  but  it  is  especially  adapted  to  storing 
material  in  the  winter  time.  Most  states  which  make  provision  for  monthly  payments 
on  material  stored  during  the  winter  time,  require  that  the  material  be  stored  in 
large  piles  near  a railroad.  The  central  unloading  and  proportioning  yard,  there- 
fore, is  in  accordance  with  state  highway  specifications,  and  insures  maximum 
payments  on  material  stored  during  the  winter  time. 

The  type  of  unloading  equipment  to  use,  depends  largely  on  the  type  of 
railroad  cars  in  which  material  is  received.  In  many  parts  of  the  country  hopper 
bottom  cars  prevail,  and  in  such  a case  a pit  can  be  excavated  beneath  the  track 
and  material  discharged  directly  into  a bucket  elevator.  In  order  to  secure 
greater  capacity  and  range  of  distribution  than  is  provided  by  the  bucket  elevator, 
derricks  or  cranes  equipped  with  clam  shell  buckets  are  much  used.  In  case  mater- 
ial is  received  in  hopper  bottom  cars,  a pit  is  excavated  to  one  side  of  the  track 
into  which  material  can  be  discharged  from  a sloping  pit  underneath  the  track. 
Material  is  then  picked  up  from  the  pit  by  means  of  the  clam  shell  bucket.  If  the 
job  is  large  enough  to  warrant  it,  a trestle  might  be  used  thru  which  material 
could  be  dumped  into  a bunker. 

Undoubtedly  the  best  type  of  unloading  apparatus  at  the  present  time  is 
a traction  crane  either  of  the  flanged  wheel  or  caterpillar  type.  Such  a crane 
equipped  with  a clam  shell  bucket , can  move  up  and  down  the  siding  and  unload 
material  anywhere  in  a long  pile.  A light  steam  shovel  equipped  with  a 30  to  35 
foot  boom,  can  handle  a 3/4  yard  clam  shell  bucket.  Such  a shovel  so  equipped  will 
cost  about  $10,000  at  the  present  time,  and  is  a very  good  piece  of  apparatus  for 
unloading  purposes.  In  selecting  unloading  equipment,  it  is  important  that  a 
long  boom  be  obtained. 

Experience  indicates  that  a 3/4  yard  clam  shell  bucket  is  the  best  all 
around  size  for  unloading  material  from  railroad  cars.  A larger  size  might  pick 
up  more  material  the  first  few  times,  but  after  that  the  larger  bucket  would  not 
take  a bigger  load  than  a 3/4  yard.  The  increased  time  required  to  "spot”  the 
larger  bucket,  also  tends  to  reduce  its  output. 

A good  operator  on  a derrick  with  a 50  or  60  foot  boom  and  a 3/4  yard 
clam  shell  bucket,  should  unload  from  8 to  10  carloads  of  material  of  35  oubic 
yards  each  in  10  hours.  A good  operator  on  a crane  should  unload  from  10  to  12 
carloads  under  the  same  conditions. 


When  bulk  cement  is  shipped  in  open  top  cars  and  is  unloaded  by  means  of 
a crane  and  clam  shell  bucket  into  a bin,  about  17  per  cent  of  the  time  of  the 
crane  is  required  for  handling  the  cement • 


I 


i 


90 


CHAPTER  XI. 


PERSONNEL  REQUIRED. 


The  personnel  required  in  highway  construction  naturally  varies  with  the 
size  of  the  job  and  with  the  type  of  equipment  employed,  as  well  as  with  the 
efficiency  and  organizing  ability  of  the  contractor.  In  comparing  the  personnel 
required  by  various  methods  of  road  building,  we  will  assume  a concrete  road  18 
feet  wide,  and  7-l/3  inches  in  average  thickness . A 14-E  mixer  handling  a 4 bag 
batch  of  1-2-3  concrete,  will  constitute  the  mixing  plant. 

Unloading  material  by  hand  from  railroad  cars  onto  the  ground,  is  but 
seldom  practiced  in  highway  construction  today.  Even  small  contractors  on  small 
jobs  generally  employ  some  mechanical  or  semi-mechanical  means. 

In  order  to  eliminate  hand  shovelers  an  "A”  frame  is  sometimes  erected 
on  one  side  the  car.  A cable  passed  thru  a sheave  attached  to  the  "A”  frame  is 
fastened  to  an  ordinary  drag  scraper,  and  material  is  scraped  out  of  the  car  onto 
the  ground  or  into  a side  hopper.  Power  for  operating  this  scraper  is  furnished 
by  means  of  a team  or  a small  gas  engine. 

To  reduce  the  waiting  time  of  haulage  equipment  at  the  material  yard  to 
a minimum,  is  a problem  to  which  contractors  have  always  devoted  a good  deal  of 
attention.  One  of  the  first  methods  of  accomplishing  this  was  by  means  of  hoppers 
attached  to  the  side  of  the  car.  Material  was  shoveled  by  hand  into  these  hoppers, 
each  of  which  contained  one  wagon  load  of  material.  A typical  hopper  of  this 
type  is  that  which  is  known  as  the  Heltzel  Lightning  Unloader,  manufactured  by 
the  Heltzel  Steel  Form  & Iron  Company,  of  Warren,  Ohio. 

Movable  hoppers  have  been  used,  into  which  material  is  unloaded  by  means 
of  a light  crane  or  derrick.  The  photograph  below  illustrates  hoppers  of  this 
type. 


MOVABLE  MATERIAL  HOPPERS,  OHS  LOAD  CAPACITY 


91 


A portable  wooden  bin  equipped  with  a bucket  elevator  or  an  elevating 
skip,  is  a type  of  unloading  apparatus  very  commonly  used  at  the  present  time  on 
small  jobs.  A typical  bin  of  this  kind  is  illustrated  by  the  photograph  on  page 
82.  A derrick  or  a crane  equipped  with  a clam  shell  bucket,  is  the  most  commonly 
used  type  of  equipment  for  unloading  material  for  highway  construction. 

In  unloading  material  by  hand  onto  the  ground  or  into  hoppers  attached 
to  the  side  of  the  car,  a fair  rate  of  operation  is  about  20  cubic  yards  of  sand 
or  15  cubic  yards  of  stone  per  man  per  10  hour  day.  If  cement  is  unloaded  direct- 
ly from  the  railroad  car  into  a truck  or  wagon,  from  3 to  4 men  will  handle  about 
300  barrels  of  cement  per  day.  The  cement  men.,  added  to  the  6 sand  shovelers  and 
12  stone  shovelers  necessary  in  unloading  sufficient  material  to  supply  a 14-E 
paving  mixer  laying  400  feet  of  18  foot  concrete  road  per  day,  makes  a total  of 
about  22  men.  A foreman  and  a water  boy  should  be  added  to  this  organization. 

In  unloading  material  by  means  of  the  drag  scraper  method,  it  is  neces- 
sary to  provide  a scraper  and  an  MA"  frame  for  sand  and  one  for  stone.  One  nan 
will  be  required  to  operate  the  scraper,  and  about  3 more  to  clean  material  out 
of  the  comers  of  the  car.  A driver  for  the  team  or  an  operator  for  the  hoisting 
engine  used  to  provide  power  for  the  scraper,  must  also  be  provided. 

Three  to  4 men  will  be  required  when  a portable  bin  with  a bucket 
elevator>or  an  elevating  3cip,  is  used  for  unloading  purposes,  in  addition  to  an 
operator  for  the  gasolene  engine.  These  men  are  needed  to  clean  out  cars,  feed 
the  elevator  or  bucket,  and  to  shift  cars. 

The  methods  of  unloading  material  described  in  the  preceding  paragraphs, 
except  the  derrick  or  crane  method,  are  not  suitable  for  highway  construction  on 
a large  scale,  and  are  mentioned  only  as  a matter  of  general  interest. 

In  determining  the  personnel  required  by  various  methods  of  road 
building,  we  will  assume  an  8 mile  concrete  road,  18  feet  wide,  with  an  unloading 
point  at  the  center.  Five  methods  of  road  building  will  be  considered,  namely, 
team  or  truck  haulage  with  material  dumped  on  the  subgrade  and  charged  into  the 
mixer  by  hand,  direct  charging  of  the  mixer  by  means  of  a 5 ton  motor  truck  with 
compartment  dump  body,  direct  charging  of  the  mixer  by  means  of  a Ford  truck  with 
special  dump  body,  the  combined  light  railway  and  motor  truck  system,  and  the 
complete  railway  system.  The  daily  output  will  be  taken  at  400  lineal  feet  of 
18  foot  concrete  road  of  a 1-2-3  mixture,  averaging  7-l/3  inches  in  thickness. 

The  quantities  required  are  as  follows: 


PER  DAY 

Cement  285  bbls.  or  54  tons 
Sand  85  cu.yds.  or  128  tons 
Stone  128  cu.yds.  or  355  tons 


TOTAL 

30,160  bbls.  or  5670  tons 
8,962  cu.yds. or  13442  tons 
13,442  cu.yds .or  18147  tons 


A light  steam  shovel  such  as  the  Erie  or  the  Thew,  equipped  with  a 30 
or  35  foot  boom,  caterpillar  traction,  and  3/4  yard  clam  shell  bucket,  will  form 
the  unloading  equipment.  The  tunnel  system  of  storing  material  will  be  used  with 
the  complete  railway  plant,  and  the  stock  pile  and  bin  method  with  the  other 
plant  s • 


The  road  we  have  under  consideration  will  require  3,016  loads  of  ce- 
ment, 5,975  loads  of  sand,  and  8,963  leads  of  stone.  This  is  based  on  an  average 


92. 


load  for  a team  of  10  "barrels  of  cement,  l-l/2  cubic  yards  of  sand,  or  l-l/2  cubic 
yards  of  stone. 

A fair  rate  of  travel  for  a team  hauling  material  over  an  ordinary  dirt 
road  is  220  feet  per  minute  or  2-1  Jz  miles  per  hour,  while  an  allowance  of  5 
minutes  for  loading  and  5 minutes  for  dumping  is  about  right.  For  loading  and 
unloading  cement,  however,  an  allowance  of  10  minutes  for  each  operation  must  be 
made  when  the  load  consists  of  10  barrels  and  2 men  are  assigned  to  this  task. 

A daily  travel  of  20  to  24  miles  is  a good  day’s  work  for  a team. 

On  the  average  haul  of  2 miles  on  this  road  a team  hauling  sand  or  stone 
will  make  a round  trip  in  106  minutes,  or  6 round  trips  per  10  hour  day.  A team 
hauling  cement  will  average  5 round  trips  per  10  hour  day.  To  haul  3,016  loads  of 
cement  at  an  average  of  5 per  day,  will  require  603  team  days,  while  to  haul 
14,938  loads  of  sand  and  stone  at  an  average  of  6 per  day  will  require  2,489  team 
days.  The  total  number  of  team  days  required  will  be  approximately  the  same 
whether  a few  teams  are  employed  for  a comparatively  long  period  of  time,  or  a 
larger  number  of  teams  for  a shorter  period  of  time.  There  is,  however,  more 
chance  for  delay  due  to  bad  weather,  etc.,  when  work  is  spread  out  over  a long 
period  of  time  than  when  it  is  completed  as  soon  as  possible.  In  the  average 
case,  the  hauling  must  be  accomplished  in  about  the  same  period  of  time  devoted 
to  laying  the  concrete. 

In  a preceding  chapter  it  was  pointed  out  that  l-l/4  miles  of  18  foot 
concrete  road  per  month  was  a good  rate  of  operation  for  a 14H3  paving  mixer, 
with  a good  organization  and  an  ample  supply  of  materials.  At  this  rate  about 
6-l/2  months  will  be  required  for  actually  placing  the  concrete  on  this  job, 
without  making  any  allowance  for  delay  due  to  waiting  on  grading  operations, 
cleaning  up,  etc.  At  a rate  of  20  working  days  per  month,  130  working  days  will 
be  obtained  in  6-l/2  months. 

Inasmuch  as  a total  of  3,092  team  days  of  work  are  necessary  to  haul 
material  to  this  job,  24  teams  must  be  assigied  to  this  operation  in  order  to 
complete  it  in  130  working  days. 


If  5 ton  motor  trucks  are  used  for  hauling  material  and  dumping  it 
directly  on  the  subgrade,  a total  of  1,134  loads  of  cement,  2,688  loads  of  sand, 
and  3,630  loads  of  stone  must  be  hauled.  Over  ordinary  dirt  roads  an  average 
speed  of  6 miles  per  hour  loaded  and  10  miles  per  hour  empty  can  be  maintained 
with  a truck  of  this  size.  An  allowance  of  5 minutes  for  loading  and  10  minutes 
for  unloading  and  getting  away,  has  been  shown  by  experience  to  be  about  right 
when  hauling  sand  and  stone.  For  hauling  cement  the  same  rate  of  speed  can  be 
maintained,  but  an  allowance  of  20  minutes  for  loading  and  20  minutes  for  unload- 
ing must  be  made.  On  the  average  haul  of  2 miles,  a truck  hauling  sand  or  stone 
should  make  a round  trip  in  47  minutes  or  13  round  trips  per  10  hour  day.  A 
truck  hauling  cement  should  make  a round  trip  in  70  minutes,  or  8 per  10  hour  day. 
To  haul  1,134  loads  of  cement  at  the  rate  of  8 per  day  will  require  142  truck 
days,  while  to  haul  6,318  loads  of  sand  and  stone  at  the  rate  of  15  per  day  will 
require  486  truck  days.  To  accomplish  the  628  truck  days  of  work  in  130  daysf 
will  require  the  services  of  5 - 5 ton  trucks. 

Five  ton  trucks  with  dump  bodies  subdivided  into  compartments  to  permit 


4 batches  to  be  carried,  are  quite  often  used  to  dump  directly  into  the  mixer 
skip.  At  a speed  of  6 mile 3 per  hour  loaded  and  10  miles  per  hour  enpty,  with  an 


93 


allowance  of  5 minutes  for  loading  and  12  minutes  for  dumping,  a truck  will  per- 
form a round  trip  on  the  average  haul  of  2 miles  in  49  minutes.  This  is  at  the 
rate  of  12  round  trips  per  10  hour  day,  enabling  a truck  to  deliver  48  batches  to 
the  mixer.  Six  trucks  are,  therefore,  needed  to  deliver  300  batches  to  the  mixer. 
The  photograph  below  illustrates  the  method  of  charging  a mixer  direct  by  means 
of  a 5 ton  truck  with  a subdivided  body* 


When  Ford  trucks  are  used  to  charge  the  mixer  direct,  an  average  speed 
of  12  miles  per  hour  both  loaded  and  empty  is  about  right,  with  an  allowance  of 
3 minutes  for  loading  and  2 minutes  for  unloading  at  the  mixer.  At  this  rate  a 
truck  will  make  a round  trip  on  the  average  haul  of  2 miles,  in  25  minutes,  or 
24  round  trips  per  10  hour  day  delivering  24  batches  and  traveling  96  miles* 
Inasmuch  as  the  mixer  requires  300  batches,  at  least  13  trucks  must  be  kept  in 
operation.  To  insure  continuous  operation,  experience  indicates  that  a stir  plus 
of  one-fourth  to  one-third  trucks  must  be  provided  on  account  of  the  severe 
service  to  which  these  light  units  are  subjected. 


FORD  TRUCKS  WITH  3FSCIAL  DUMP  BODY 


DIRECT  CHARGING  OF  MIXER  WITH  5 TON  TRUCK 


94 


In  operating  a combined,  light  railway  and  motor  truck  plant,  the  mixer 
is  started  at  the  point  nearest  the  material  yard  and  is  supplied  entirely  by 
railway  -until  the  end  of  the  l-l/2  miles  of  track  is  reached.  At  a rate  of  l-l/4 
miles  per  month,  the  mixer  will  require  1.2  months  or  36  days  to  reach  the  end  of 
the  track.  State  specifications  permit  hauling  over  the  concrete  after  the  expira- 
tion of  21  days,  and  inasmuch  as  the  mixer  is  assumed  to  operate  only  20  days  per 
month,  or  two-thirds  of  the  time,  about  three-fourths  mile  of  concrete  will  be  21 
days  old  by  the  time  the  mixer  reaches  the  end  of  the  track.  This, then,  is  the 
minimum  truck  haul.  The  maximum  truck  haul  will  be  2-1/2  miles  in  this  case, 
while  the  average  truck  haul  will  be  1-5/8  miles. 

Inasmuch  as  the  trucks  operate  at  all  times  over  a finished  road,  they 
should  average  a speed  of  10  miles  per  hour  both  loaded  and  empty.  Experience 
indicates  that  an  allowance  of  5 minutes  for  loading  4 batch  boxes  and  10  minutes 
for  transferring,  is  ample.  At  this  rate  a truck  will  make  a round  trip  on  the 
average  haul  of  1-5/8  miles  in  34  minutes,  or  18  per  10  hour  day  delivering  72 
batches.  An  average  of  from  4 to  5 trucks  will,  therefore,  be  required  on  this 
job,  when  operating  a combined  light  railway  and  motor  truck  system  . In  a comr 
bined  light  railway  and  motor  truck  system,  the  trucks  are  generally  rented.  On 
this  particular  job  they  will  not  be  needed  during  the  construction  of  the  first 
l-l/2  miles  of  road  on  each  side  of  the  material  yard,  inasmuch  as  the  railway 
will  serve  the  mixer  on  this  portion  of  the  work.  Trucks  will  be  required  during 
the  construction  of  only  about  two-third3  of  this  road.  In  reality,  therefore, 
the  average  number  of  trucks  required  thruout  the  life  of  this  job,  is  only  3. 


DERRICK  ON  WAGON  FOR  TRANSFERRING  BATCH  BOXES 


On  the  railway  portion  of  the  combined  light  railway  and  motor  truck 
haul,  the  average  haul  from  the  transfer  point  to  the  mixer  will  be  1 mile.  As 
previously  shown,  1-6  ton  locomotive  is  generally  sufficient.  The  railway 
operating  personnel,  therefore,  will  consist  of  1 locomotive  operator  and  1 train 
man. 

A speed  of  6 miles  per  hour  and  an  allowance  of  5 minutes  for  sv/itching 
trains  at  the  mixer  and  5 minutes  at  the  material  yard,  is  a proper  basis  on  which 
to  proportion  the  amount  of  rolling  stock  required  for  a complete  railway  plant. 
Assinning  grades  do  not  exceed  7 per  cent,  we  can  use  a 6-car,  12-batch  train, 
splitting  it  on  all  grades  over  4 per  cent.  On  the  average  haul  of  2 miles,  the 
round  trip  can  be  accomplished  in  50  minutes  or  12  per  10  hour  day.  Inasmuch  as 


95 


each  train  carries  12  ‘batches,  1 locomotive  will  deliver  144  batches  to  the  mixer 
per  day.  Two  locomotives,  by  speeding  up  a trifle  or  occasionally  using  a little 
sand  so  as  to  permit  hauling  a 7 car  train,  can  easily  deliver  300  batches  to  the 
mixer.  In  proportioning  light  railway  equipment  it  is  customary,  as  pointed  out 
before,  to  base  the  rolling  stock  upon  a length  of  haul  equal  to  three-fourths  of 
the  maximum.  In  this  comparison,  however,  the  haulage  equipment  will  be  based 

upon  the  average  haul,  inasmuch  as  this  is  the  haul  assumed  for  the  other  methods. 

In  charging  a mixer  with  a 4 bag  batch  of  materials  for  1-2-3  concrete 
by  means  of  •wheelbarrows  and  shovelers,  the  following  organization  is  generally 
required  as  a minimum: 

3 - men  wheeling  sand 

2 - men  shoveling  sand 

4 - men  wheeling  stone 

4 - men  shoveling  stone 

3 - men  handling  cement 

1 - man  handling  empty  bags 

17  - men 

In  charging  a mixer  direct  by  means  of  trucks  or  by  means  of  light 
railway  haulage,  2 and  3 men  respectively  are  required  at  the  charging  end  of 
the  mixer.  Hie  Ford  truck  method,  however,  requires  2 additional  men  at  the 
turntable • 

When  material  is  dumped  on  the  subgrade  or  when  hauling  is  performed  over 
it,  the  subgrade  must  be  trimmed  by  hand.  In  order  to  trim  a sufficient  amount  of 

subgrade  by  hand  to  enable  400  feet  of  road  to  be  laid  per  day,  a subgrade  gang 

of  10  to  12  men  and  a sub-foreman  is  required.  Hie  unobstructed  subgrade  charac- 
teristic of  light  railway  haulage,  permits  machine  trimming  of  the  subgrade.  Hie 
subgrader  is  generally  pulled  by  means  of  a road  roller,  and  sufficient  subgrade 
for  a day’s  run  can  be  trimmed  in  a few  hours.  In  operating  the  subgrader,  men 
engaged  in  curing  the  concrete  or  in  maintaining  the  railway  track  are  brought 
back  to  assist  in  the  operation.  Six  men  will  trim  all  the  subgrade  required  for 
a day’s  run  in  3 or  4 hours  with  a subgrader.  This  is  equivalent  to  an  average 
of  about  2 men  for  10  hours*  The  subgrader  is  sometimes  pulled  with  a tractor* 


<5 


96 


When  the  mixer  is  aharged  direct  by  means  of  a 6 ton  or  Ford  truck 
method,  the  combined  light  railway  and  motor  truck  method,  or  the  complete  railway 
method,  btilk  cement  can  readily  be  used.  The  method  of  unloading  bulk  cement  and 
handling  it  at  the  material  yard,  has  been  outlined  in  the  previous  chapter.  An 
average  of  about  2 men  is  generally  sufficient  to  unload  bulk  cement  at  a rate 
which  will  permit  building  400  feet  of  18  foot  concrete  road  in  10  hours.  When 
bagged  cement  is  used,  an  average  of  about  4 men  is  required. 

It  will  be  assumed  that  a finishing  machine  is  used  on  all  these  methods 
so  that  the  personnel  required  for  setting  forms  and  for  finishing  will  be  the 
same  for  all. 

The  personnel  required  for  a job  of  the  kind  we  have  assumed,  under 
average  conditions,  is  about  as  follows: 


SYSTEM 


HAND  CHARGING 

DIRECT  CHARGING 

Team 

5 Ton 
Truck 

Ford 

Truck 

5 Ton 
Truck 

Comb.  Rwy. 
and  Truck 

Complete 

Railway 

Material  Yard 

Crane  Operator 

1 

1 

1 

1 

1 

1 

Crane  Fireman 

1 

1 

1 

1 

1 

1 

Bucket  Man 

1 

1 

1 

1 

1 

1 

Car  clean-up  men 

2 

2 

2 

2 

2 

2 

Unloading  bagged  cement 

4 

5 

* 

* 

* 

* 

Unloading  bulk  cement 

* 

* 

2 

2 

2 

2 

Bin  Gate  Men 

2 

1 

2 

1 

1 

♦ 

Tunnel  Men 

* 

* 

♦ 

* 

* 

2 

Water  Boy 

1 

1 

1 

1 

1 

1 

Hauling  Material 

Team  Drivers 

24 

* 

* 

* 

* 

* 

Stable  Men 

4 

* 

* 

* 

* 

* 

Truck  Drivers 

* 

5 

13 

6 

3 

* 

Garage  Men 

* 

2 

2 

2 

* 

* 

Locomotive  Operators 

* 

* 

* 

* 

1 

2 

Train  Men 

* 

* 

* 

* 

1 

2 

Man  to  fill  radiators 

* 

* 

1 

* 

* 

* 

Turntable  Men 

* 

* 

2 

* 

♦ 

* 

Transfer  Point  Men 

* 

* 

* 

* 

3 

* 

Track  Men 

* 

* 

* 

* 

2 

3 

Material  Yard  and  Hauling 

Foremen 

1 

1 

1 

1 

1 

1 

Mixing  and  Placing  Concrete 

Mixer  Operator 

1 

1 

1 

1 

1 

1 

Mixer  Fireman 

1 

1 

1 

1 

1 

1 

Finishing  Mach.  Operator 

1 

1 

1 

1 

1 

1 

Concrete  Spreaders 

3 

3 

3 

3 

3 

3 

Charging  mixer 

17 

17 

2 

2 

3 

3 

Setting  Forms 

3 

3 

. 3 

3 

3 

3 

97. 


HAM)  CHARGING  DIRECT  CHARGING- 


Team 

5 Ton 

Ford 

5 Ton 

Comb.  Rwy. 

Complete 

Truck 

Truck 

Truck 

and  Truck 

Railway 

Mixing  and  Placing  Concrete 

Trimming  Subgrade 

12 

12 

12 

12 

2 

2 

Sub-foreman  on  subgrade 

1 

1 

1 

1 

* 

* 

Roller  Operator 

1 

1 

1 

1 

1 

1 

Curing  Concrete 

4 

4 

4 

4 

4 

4 

Pump  Man 

1 

1 

1 

1 

1 

1 

Pipe  Man 

1 

1 

1 

1 

1 

1 

Water  Boy 

1 

1 

1 

1 

1 

1 

Watchman 

1 

1 

1 

1 

1 

1 

Foreman 

1 

1 

JL. 

1 

1 

JL 

89 

67 

62 

50 

42 

41 

In  addition  to  the  operating  personnel  listed  above,  a superintendent  is  generally 
in  charge  of  the  entire  job.  A time -keeper,  a material  cleric,  a general  office 
man  for  the  field  office,  and  a cost  keeper  are  provided  on  the  average  fair  sized 
job.  A garage  for  field  repairs  with  1 mechanic  and  helper,  must  be  provided  in 
order  to  keep  the  motor  trucks  in  shape.  Particularly  is  this  true  with  the  Ford 
trucks,  for  they  travel  an  average  of  96  miles  per  day.  The  average  travel  of  the 
5 ton  trucks  is  56  miles.  No  garage  men  are  provided  for  the  combined  light  rail- 
way and  motor  truck  plant,  inasmuch  as  the  motor  trucks  are  generally  rented  and 
the  owner  provides  for  their  repair  in  his  rental  charge.  A blacksmith  and  a 
helper  are  generally  necessary  on  a job  of  this  size. 

Each  contractor  has  his  own  arrangement  for  paying  his  men,  but  all  of 
them  generally  have  a certain  number  " straight-time”  men.  These  men  are  paid  the 
regular  wage  on  rainy  days  as  well  as  working  days.  Most  contractors  carry  a few 
men  thruout  the  year  as  a nucleous  for  their  organization,  generally  the  foremen 
and  sub-foremen,  the  mechanics,  the  crane  operator,  and  the  mixer  operator.  The 
foremen  and  the  superintendent  are  paid  either  by  the  month  or  by  the  year,  while 
the  rest  of  the  personnel,  except  the  ”strai git -time”  men,  are  paid  only  for  the 
actual  time  they  work.  Frequently  the  office  force,  or  at  least  a part  of  it, 
are  carried  thruout  the  year.  Most  progressive  contractors  employ  an  engineer 
for  the  purpose  of  checking  the  quantities  shorn  on  the  plans,  and  for  doing  such 
other  engineering  work  as  is  necessary. 


. 


- 


98 


CHAPTER  XII. 
COST  OF  OPERATION. 


One  of  the  most  common  mistakes  in  highway  construction,  in  judging  the 
merits  of  a plan  of  operation,  is  to  give  undue  consideration  to  the  cost  of 
hauling,  regardless  of  the  fact  that  hauling  is  hut  one  of  a number  of  coordinated 
functions  which  must  he  performed,  though  it  is  no  doubt  one  of  the  most  important. 
If  hauling  were  the  only  operation  to  be  performed  in  road  building,  then  the  cost 
per  ton  mile  would  be  the  proper  criterion  upon  ■which  to  base  judgment.  In  order 
to  correctly  judge  of  the  merits  of  any  system  of  road  building,  all  of  the  oper- 
ations involved  must  be  considered  as  a whole.  It  is  manifestly  false  economy  to 
adopt  a plan  of  operation  because  the  cost  of  hauling  is  lower  than  by  some  other 
plan,  but  where  the  losses  due  to  extra  labor  involved  in  charging  the  mixer  and 
trimming  the  subgrade,  loss  of  material  due  to  dumping  on  the  subgrade,  loss  due 
to  extra  concrete  because  of  inaccurate  subgrade,  etc.  will  more  than  absorb  any 
saving  in  the  cost  of  hauling.  The  actual  cost  of  hauling  per  ton  mile  by  the 
combined  light  railway  and  motor  truck  system  on  a small  job, 3 or  4 miles  long, 
is  frequently  greater  than  it  would  be  if  teams  or  trucks  were  hired  by  the  day. 

The  economy  effected  in  charging  the  mixer,  trimming  the  subgrade,  reduction  of 
delay  due  to  wet  weather,  etc.,  by  the  comb ined  light  railway  and  motor  truck 
system,  however,  will  more  than  compensate  for  the  increased  cost  of  hauling.  In 
spite  of  all  this,  however,  undue  emphasis  is  frequently  placed  on  tie  cost  of 
hauling  per  ton  mile. 

Another  common  and  costly  mistake  frequently  made,  is  to  assume  a uniforn 
cost  per  ton  mile  for  hauling  regardless  of  the  length  of  haul.  The  cost  of  haul- 
ing per  ton  mile  varies  inversely  with  the  length  of  haul.  When  a comparatively 
expensive  plant,  such  aslight  railway  or  motor  truck,  is  used  on  a short  haul,  the 
actual  cost  of  hauling  per  ton  mile  is  frequently  greater  than  by  team.  As  the 
haul  increases,  however,  the  railway  and  truck  cost  finally  becomes  less  than  that 
by  team.  A cost  per  ton  mile  for  hauling  is  absolutely  no  good,  unless  the  length 
of  haul  and  percentage  of  waiting  time  involved  is  also  given. 

The  cost  of  hauling,  like  any  other  cost,  varies  with  local  conditions, 
with  the  length  of  working  season  and  weather  conditions,  and  with  the  managing 
ability  of  the  contractor.  It  is  obvious  that  the  unit  cost  of  hauling  in  hilly 
country  or  on  roads  of  a certain  character,  will  differ  considerably  from  the  cost 
in  level  country  or  on  roads  of  another  character.  In  a part  of  the  country  where 
the  working  season  is  longer  than  it  is  in  another  part,  the  unit  cost  of  hauling 
will  be  less.  Plant  and  overhead  charges  must  be  provided  for  during  the  working 
season,  no  matter  how  short  it  may  be.  A greater  amount  of  work  can  be  performed 
in  a long  season  than  in  a short  one,  and  in  a long  season  fixed  charges  can  be 
spread  over  greater  mileage  than  in  a short  season.  The  unit  cost  of  hauling  in 
a wet  climate,  is  generally  greater  than  in  a dry  climate.  On  certain  jobs  it 
might  be  necessary,  for  business  reasons,  to  charge  off  a greater  percentage  for 
depreciation  than  on  other  jobs,  and  in  such  a case  the  unit  cost  of  hauling  will 
be  increased.  Equipment  purchased  during  a period  of  unusually  high  prices, 
should  be  charged  off  at  a greater  rate  than  equipment  purchased  during  a normal 
or  a rising  market.  All  of  these  factors  influence  unit  costs  very  materially, 
and  on  this  account  a contractor  should  use  great  caution  with  figures  from  some 
other  job  or  part  of  the  country  where  conditions  are  not  fully  known  to  him. 

Data  issued  by  manufacturers  of  equipment  frequently  oraitSy,  many  vital  factors 
which  go  to  make  up  a cost,  and  this  data  should  be  used  by  contractors  only  after 


99, 


careful  scrutiny. 

In  the  final  analysis  cost  is  merely  a relative  term,  and  is  not  by  any 
means  absolute  or  fixed.  The  cost  to  one  man  of  performing  a certain  work,  might 
be  entirely  different  from  the  cost  to  some  one  else,  on  account  of  certain 
peculiarities  of  temperament  or  conditions.  It  is  again  desired  to  emphasize, 
therefore,  that  any  cost  obtained  under  conditions  not  absolutely  known,  should  be 
used  only  as  a guide  and  with  caution. 

The  term  cost  is  a composite  one,  including  a large  number  of  elements. 
All  too  frequently  the  inexperienced  man  fails  to  place  proper  emphasis  on  some  of 
the  more  or  less  intangible  elements,  because  his  vision  is  obscured  by  the  con- 
crete elements  of  labor  and  materials.  While  it  is  true  that  the  cost  of  labor 
and  materials  generally  forms  the  greater  part  of  the  final  cost,  it  is  equally 
true  that  failure  properly  to  consider  other  elements  will  result  in  a loss  even 
though  the  cost  of  labor  and  material  has  been  properly  estimated.  Or  if  the 
other  elements  which  make  up  a cost  in  addition  to  labor  and  material  have  been 
kept  in  mind,  the  mistake  is  frequently  made  of  providing  for  them  insufficiently. 

Perhaps  the  element  of  plant  charges  is  more  frequently  under-estimated 
than  any  of  the  other  so-called  intangible  elements.  The  danger  of  this  practice 
is  due  to  the  fact  that  it  is  generally  not  discovered  for  a number  of  years,  vi  th 
the  result  that  the  apparent  profit  earned  during  the  previous  years  is  very  con- 
siderably reduced  or  is  really  not  a profit  at  all.  Failure  properly  to  estimate 
other  elements  of  a cost  generally  becomes  apparent  at  least  by  the  completion  of 
the  job,  but  failure  to  make  proper  plant  charges  is  not  apparent  at  once  and  is, 
therefore,  much  more  dangerous. 

Plant  charges  consist  of  depreciation  on  the  equipment,  interest  on  the 
investment,  field  repairs,  shop  repairs,  storage  charges,  insurance,  and  obsoles- 
cence. These  charges  are  generally  expressed  in  terms  of  a percentage  of  the 
initial  cost  of  the  equipment.  The  proper  percentage  to  be  charged  depends  upon 
the  type  of  equipment  and  whether  it  is  special  or  standard,  upon  the  job  and  the 
conditions  under  which  it  is  employed,  and  upon  its  second  hand  value  and  scrap 
value.  A piece  of  special  equipment  purchased  for  a particular  job, which  will 
probably  be  of  but  little  further  use,  should  obviously  be  charged  entirely  to 
this  one  job.  The  type  of  equipment  will  affect  the  plant  charge  very  materially, 
for  it  is  apparent  that  a steam  shovel  or  a heavy  earth  moving  car  will  last 
longer  than  a concrete  mixer  or  a finishing  machine.  If  equipment  is  operated  on 
a double  shift,  the  rate  of  depreciation  and  the  amount  of  repairs  will  naturally 
be  greater  than  if  it  is  operated  on  a single  shift.  A steam  shovel  or  cars 
working  in  rock,  will  naturally  wear  out  faster  than  if  working  in  earth.  Some 
equipment  will  have  a considerable  scrap  value,  while  other  equipment  will  have 
practically  none.  Some  equipment  will  have  a higher  second  hand  value  and  a 
broader  second  hand  market,  than  other  equipment.  Some  equipment  might  have  been 
purchased  during  a period  of  high  prices,  while  other  equipment  might  have  been 
purchased  during  a period  of  normal  or  low  prices.  All  of  these  factors  must  be 
considered  and  proper  weight  given  to  them,  in  deciding  upon  plant  charges. 

The  estimated  rate  of  depreciation  is  not  always  based  upon  the  probable 
life  of  the  equipment,  but  frequently  upon  the  time  in  which  the  business  judgment 
of  the  contractor  indicates  that  he  must  recover  his  investment.  For  instance. 


most  concrete  mixers  will  last  for  6 or  7 years,  but  it  is  common  practice  to  base 
the  rate  of  depreciation  in  computing  plant  charges  upon  a life  of  4 years. 


« ' 


♦ 


100. 


More  mistakes  are  made  in  estimating  plant  charges  than  in  any  other 
element  of  cost,  and  a considerable  amount  of  experience  is  required  for  an  intelli 
gent  estimate.  A copy  of  a "Guide  for  Estimating  Construction  Plant  Charges"  re- 
cently issued  by  the  Associated  General  Contractors  of  America,  will  be  found  in 
the  appendix.  This  Guide  represents  the  consensus  of  opinion  of  a considerable 
number  of  contractors  as  to  what  proper  plant  charges  should  be. 

One  thing  which  must  always  be  kept  in  mind,  is  that  plant  charges  must 
be  earned  during  the  construction  season^no  matter  how  short  it  may  be.  For 
instance,  a contractor  migdit  purchase  motor  trucks  to  be  used  in  road  building 
during,  say,  6 months  of  the  year.  He  might  charge  only  half  of  the  yearly  plant 
charges  to  the  road  work,  assuming  that  the  other  half  will  be  earned  during  the 
winter  time  in  performing  other  work  such  as  hauling  coal.  Unless  he  has  absolute 
assurance  that  he  will  be  able  to  obtain  work  for  his  trucks  outside  of  his  road 
work,  such  a procedure  is  very  risky.  Even  though  he  has  proper  assurance  that  he 
can  haul  coal  during  the  winter  time,  it  is  not  good  business  for  him  to  depend 
upon  an  auxiliary  operation  to  carry  part  of  the  plant  charges  on  equipment  pur- 
chased primarily  for  road  work.  If  equipment  is  purchased  primarily  for  accom- 
plishing some  purpose,  all  of  the  plant  charges  should  be  charged  to  it.  If  this 
can  not  be  done  without  making  the  cost  excessive,  then  obviously  the  equipment 
is  not  the  proper  kind  for  the  purpose  in  mind. 

A contractor  is  frequently  confronted  with  the  problem  of  deciding  just 
what  proportion  of  the  yearly  plant  charges  is  to  be  assigned  to  some  one  job. 

This  job  might  be  secured  early  in  the  yaar,  and  might  not  be  of  quite  sufficient 
size  to  keep  him  busy  during  the  entire  season.  He  must  then  decide  whether  to 
assign  all  the  plant  charges  for  the  year  to  this  one  job,  or  whether  to  assign 
only  a portion  in  the  expectation  of  securing  another  contract  which  will  absorb 
the  remainder.  The  decision  in  this  matter  must  be  based  upon  local  conditions, 
and  upon  the  experience  and  judgment  of  the  individual.  If  all  the  yearly  plant 
charges  are  assigned  to  the  first  job,  the  cost  might  be  so  high  as  to  preclude 
securing  the  contract,  while  if  only  a part  is  charged  to  the  first  job, the  risk 
is  incurred  of  not  securing  another  job  to  carry  the  remainder. 

In  addition  to  the  plant  charges,  there  are  a number  of  other  important 
charges  ■which  go  to  make  up  a cost.  Some  of  these  charges  are  directly  applicable 
to  each  job,  while  others  are  general  charges  which  must  be  pro-rated  among  the 
various  jobs.  The  cost  of  erecting  bins  and  tunnels  and  dismantling  them,  loading 
and  unloading  equipment,  freight  on  equipment  to  and  from  the  job,  the  cost  of 
erecting  and  operating  the  field  office,  certain  traveling  expenses,  etc., are 
generally  directly  chargeable  to  each  job.  If  bins  and  tunnels  are  so  constructed 
that  they  can  be  dismantled  and  moved  from  one  job  to  another,  it  would  be  proper 
to  assign  a certain  proportion  for  depreciation,  etc.,  to  each  job.  When  equipment 
is  shipped  to  a job,  it  is  seldom  known  -whether  it  will  be  re  shipped  from  that  job 
to  another  one  or  back  to  the  contractor's  yard.  It  is  generally  wise,  therefore, 
to  charge  freight  both  ways  from  the  contractor’s  yard  to  the  job. 

When  a camp  is  operated  b^  the  contract  system,  the  cost  to  the  con- 
tractor is  generally  fixed.  A well  operated,  sanitary  camp,  is  the  best  precau- 
tion a contractor  can  take  to  insure  an  adequate  supply  of  efficient  and  contented 
labor.  Rather  than  run  the  risk  of  a poor  camp  by  contracting  for  its  operation, 
it  is  generally  better  for  a contractor  to  operate  the  canp  himself.  Even  though 
a sufficient  charge  cannot  be  made  for  board  and  room  to  make  the  camp  self-sus- 
taining, it  is  always  a good  investment  to  maintain  a good  camp  and  charge  the 


loss  to  "overhead". 


101 


The  term  "overhead"  represents  the  least  tangible  of  the  many  elements 
which  comprise  a cost*  "Overhead"  can  really  he  divided  into  two  general  classes, 
namely,  "job  overhead"  and  "general  overhead"*  "Job  overhead"  includes  super- 
intendents,  field  office  expense,  traveling  expense,  watchmen,  timekeepers , cost 
keeper,  clerks,  telephones,  stationery,  lights,  and  all  other  costs  on  a job  not 
directly  assignable  to  some  other  element.  "General  Overhead"  includes  the 
executive  and  administrative  expenses  of  operating  the  general  office,  cost  of 
securing  work,  attending  conventions,  salaries  of  employees  during  winter  months, 
feed  of  stock  during  winter  months,  and  all  the  expenses  not  directly  attributable 
to  some  particular  job.  "General  overhead"  is  pro-rated  among  the  various  jobs 
in  accordance  with  the  experience  and  judgment  of  the  contractor,  and  naturally 
varies  with  particular  conditions  and  organization.  The  larger  the  organization 
the  larger  the  "overhead"  as  this  is  one  of  the  penalties  of  size* 

Each  contractor  generally  has  his  own  cost  system,  which  he  considers  to 
be  more  or  less  adapted  to  his  own  peculiar  conditions  and  problems.  This  of 
course  is  frequently  so,  and  no  attempt  will  be  made  in  this  thesis  to  enter  into 
a detailed  discussion  of  various  cost  keeping  systems.  The  Wisconsin  Highway 
Department  has  recently  prepared  a schedule  for  highway  contractors  containing 
the  many  elements  of  cost  involved  in  road  building,  a copy  of  which  will  be  found 
in  the  appendix.  Bulle tin  #660,  of  the  United  States  Department  of  Agriculture, 
entitled  "Highway  Cost  Keeping" , treats  of  cost  keeping  forms  and  methods.  This 
bulletin  can  be  secured  from  the  Superintendent  of  Documents  of  the  Government 
Printing  Office,  in  Washington,  D.  C. 

While  it  is  not  desired  to  enter  into  a detailed  discussion  of  methods 
of  cost  keeping,  still  it  is  believed  to  be  desirable  to  point  out  some  of  the 
essential  features  which  a good  system  should  include.  The  cost  of  fuel  and  oil 
should  be  kept  separate,  as  well  as  the  cost  of  coirmon  labor  and  the  cost  of 
skilled  labor.  The  cost  of  foremanship  should  be  kept  separate  from  the  cost  of 
labor,  because  the  proportionate  cost  due  to  foremanship  varies  with  each  job* 

The  "job  overhead"  should  be  kept  separate  from  the  "general  overhead"  and  the 
cost  of  securing  business,  such  as  looking  over  work,  making  out  bids,  advertising, 
etc*7  should  be  kept  by  itself.  The  cost  of  superintendents,  time  keepers,  clerks, 
watchmen,  books  and  stationery,  field  office  expense,  etc*? should  all  be  kept 
separate.  Above  all,  full  and  complete  data  concerning  the  conditions  surrounding 
a job  should  be  recorded.  Photographs  will  help  materially  in  bringing  to  mind 
conditions  years  after  the  work  has  been  completed,  and  should  be  liberally  used. 
Cost  data  is/all  too  often  rendered  valueless  by  failure  properly  and  sufficiently 
to  describe  the  prevailing  conditions  when  it  was  obtained,  and  much  of  it  is  not 
properly  subdivided  or  analyzed  so  as  to  permit  it  to  be  applied  to  other  work  of 
like  or  similar  character.  Too  much  emphasis  cannot  be  placed  upon  the  absolute 
necessity  of  providing  full  and  complete  data  to  accompany  information  on  cost, 
if  this  information  is  to  be  of  much  value  after  the  figures  are  "cold"* 

A oommon  practice  in  estimating  cost  is  to  estimate  first  the  unit  cost, 
and  then  to  obtain  the  total  cost  by  multiplying  the  unit  cost  by  the  number  of 
units.  In  certain  work,  such  as  earth  work,  this  is  the  method  that  must  general^ 
be  used,  but  in  hauling,  mixing  concrete,  or  unloading  material,  a better  method 
is  to  estimate  the  total  cost  and  then  obtain  the  unit  cost  from  the  total  if 
desired.  For  instance,  in  estimating  the  cost  of  placing  concrete,  contractors 
frequently  figure  the  daily  cost  per  square  yard*  Certain  additions  must  then  be 
made  to  provide  for  delays  due  to  rain,  loss  due  to  inaccurate  subgrade, etc*  and 
inasmuch  as  the  units  involved  are  small,  an  error  of  a few  cents  will  represent  a 
considerable  percentage  of  the  cost.  A better  method  is  to  estimate  the  total  time 
and  total  cost  required  to  complete  the  work,  making  such  allowance  for  delay  due 


102 


1 


to  wet  weather,  starting  and  stopping  the  job,  moving  the  material  yard,  lack  of 
material,  etc.  as  experience  and  judgment  dictates.  Proper  allowance  can  readily 
he  made  for  loss  of  material,  straight  time  men,  etc#  If  the  method  of  estimating 
hy  totals  is  followed,  there  is  less  chance  of  improperly  providing  for  contin- 
gencies than  in  the  method  of  estimating  hy  units# 

Sometimes  several  unloading  points  are  available,  and  the  question 
arises  as  to  how  much  of  the  road  lying  between  two  of  them  is  to  he  constructed 
with  material  hauled  from  each.  The  problem  is  further  complicated  hy  the  fact 
that  the  cost  of  establishing  one  material  yard  is  frequently  greater  than  the 
cost  of  establishing  another,  and  the  cost  of  material  at  one  point  is  greater 
than  it  is  at  another.  The  general  rule  of  dividing  the  road  so  as  to  equalize 
the  maximum  haul  from  each  material  yard,  must,  therefore,  be  changed  to  dividing 
the  road  so  that  the  unit  cost  of  material  from  either  yard  at  the  dividing  point 
is  the  same.  This  rule  must  sometimes  be  modified  considerably  in  order  to  adapt 
the  equipment  on  hand  to  the  job,  to  eliminate  grades  opposed  to  the  leaded  train, 
etc.  It  is  generally  worth  while,  however,  to  determine  the  points  of  equal  cost 
on  a road  and  to  adhere  to  them  as  closely  as  is  practical,  for  material  is  fre- 
quently hauled  from  one  yard  when  it  could  be  more  economically  hauled  from  another 

The  problem  of  determining  the  point  of  equal  cost  is  not  involved  in 
that  of  determining  the  number  of  unloading  points  to  use,  for  a decision  in  this 
respect  should  have  already  been  reached.  In  determining  the  point  of  equal  cost, 
it  is  obvious  that  the  increased  cost  of  establishing  one  naterial  yard  over  that 
of  establishing  another  must  be  absorbed  by  the  tonnage  of  material  hauled  from 
that  yard. 

In  order  to  illustrate  the  method  of  dividing  a road  when  material  is 
hauled  from  two  unloading  points,  we  will  consider  a road  such  as  that  shown  in 
the  sketch  below. 


Material  was  available  on  railroad  sidings  at  points  "A”  and  "C",  and 
the  cost  of  hauling  from  either  unloading  point  to  the  road  "BD"  was  estimated  at 
$0.40  per  ton  mile.  A mixer  was  started  at  point  "BH  and  the  problem  was  to 
determine  how  much  road  to  build  with  material  hauled  from  "A”  and  how  much  with 
material  hauled  from  ”C".  A siding  was  already  in  place  at  "C”,  but  an  expenditure 
of  $3, 000  was  necessary  to  provide  a siding  at  "A".  The  combined  light  railway 
and  motor  truck  system  of  haulage  was  used.  The  material  required  was  as  follows: 

Cement  3,760  bbls.  or  718  tons  per  mile;  5,026  tons  per  7 miles 

Sand  1,120  cu#yds#or  1,680  tons  per  mile;  11,760  tons  per  7 miles 

Stone  1,680  cu.yds.or  2,270  tons  per  mile:  15.890  tons  per  7 miles 

4,668  tons  32,676  tons 

The  cost  of  material  wa3  approximately  as  follows,  the  cement  price  per 
ton  being  derived  from  a price  of  $2#50  per  barrel  and  a weight  of  376  pounds. 


103. 


Cement  per  ton 
Sand  per  ton 
Stone  per  ton 


POINT  "A" 
$13.30 
0.60 
2.00 


POINT  11 0" 
$13.30 
1.25 
2.00 


The  proportions  of  1-2-3  by  volume  are  equivalent  to  1.00-2.36-3.19  by 
weight,  based  upon  a weight  of  276  pounds  per  barrel  of  cement,  3,000  pounds  per 
cubic  yard  of  sand,  and  2#700  pounds  per  cubic  yard  of  stone.  The  weighted  mean 
cost  of  material  at  each  point  is,  therefore,  as  follows: 


POINT  "A" 

$13.30 
0.60 
2.00 


1.00  x 
2.36  x 
S.tl.9  x 

6.55 


$13.30 

1.42 

6.38 

$21.10 


POINT  »C» 

1.00  x $13.30 
2.36  x 1.25 
3.19  x 2.00 

6.55 


= $13.30 

= 2.95 

= 6.38 


$42*65 


$21.10  I 

6.55 


$3.22,  the  weighted 
mean  cost  per  ton 
at  "A" 


$22.65 

6.55 


$3.45,  the  weighted 
mean  cost  per  ton 
at  "C" 


Let  X represent  the  mileage  of  road  to  be  constructed  with  material 
hauled  from  "A",  and  Y the  mileage  to  be  constructed  from  "C".  The  tonnage  of 
material  hauled  from  "A",  therefore,  equals  4,668  X.  The  weighted  mean  cost  of 
material  per  ton  at  "A"  is  $3.22,  while  the  cost  at  "BM,  after  hauling  1 mile, 
is  $3.62.  The  weighted  mean  cost  of  material  at  ”0"  is  $3.45,  while  the  weighted 
mean  cost  at  "D”,  after  hauling  3 miles,  is  $4.65.  The  cost  of  material  hauled 
from  "AM  at  any  point  along  the  road  distant  X from  "B" , will  be  $3.62  plus 

4^668°X  plus  $0#4°  x eciuals  $3.62  plus  plus  $0.40  X.  The  cost  of  material 

hauled  from  '’C",  at  any  point  Y from  "DM,  is  $4.65  plus  $0.40  X.  Equating  these 
expressions  gives  a value  of  4.62  miles  for  X.  In  other  words,  under  the  condi- 
tions assumed,  material  hauled  4.62  miles  from  point  "B",  is  equal  in  cost  to 
material  hauled  2.38  miles  from  point  "D".  This,  therefore,  indicates  the  mileage 
of  road  to  be  built  with  material  from  each  unloading  point,  in  the  absence  of 
other  modifying  conditions.  If  a complete  railway  system  were  employed,  a division 
of  the  road  such  as  that  indicated  above  would  involve  more  equipment  than  if  the 
maximum  haul  from  each  point  was  equalized.  In  such  a case  it  rai^it  be  more 
economical  to  divide  the  road  so  as  to  reduce  the  amount  of  equipment  required, 
rather  than  to  divide  it  strictly  in  accordance  with  the  point  of  equal  cost. 

The  accompanying  graph  illustrates  a graphical  method  of  determining  the 
point  of  equal  cost.  The  advantage  of  the  graphical  method  is  that  it  readily  in- 
dicates the  extra  cost  involved,  -when  material  is  hauled  beyond  the  point  of  equal 
cost.  For  instance, in  the  example  shown  above,  suppose  that  it  is  desired  to 
determine  the  increased  cost  due  to  building  3^-  miles  of  road  from  HC”  rather  than 
the  2.38  miles  indicated  by  the  curve.  By  continuing  the  curve  representing  the 
cost  of  mterial  hauled  from  point  "O”  to  the  3-1  Jz  mile  point,  we  see  that  the 
unit  cost  would  be  $6.10  per  ton  rather  than  the  $5.20  when  hauled  from  ’'A".  The 
area  of  the  triangle  shown  by  the  cross-hatching  gives  the  total  increase  in  cost, 
when  the  altitude  is  taken  in  terms  of  tons  of  material.  In  this  particular  case 
the  increased  cost  would  be  $6.10  minus  $5.20  times  (4,668  x 1.12)  times  1 Jz 
equals  $2,362.00.  A study  of  this  character  will  enable  the  contractor  to  as- 
certain whether  the  increased  cost  is  justified  by  the  plan  he  has  in  mind. 


I 


IS8SSBS88S88! 


IBBI 


IBBI 


IBBI 


(■■■■■■■■■■■I 


IIIRHIIIIIIHP 


t xi  • w w IB  H 15  !E IE  15  3K H W r ® ® ■»  'M  ivRWlmxi »/  -w  *v  1 . 

!■■«■■■■■■■■■■*■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■ 

IBBBBHBBB  BBBBBBBBBBSBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBaK  «■■■■■■■■■■■■■■■■■■■ 
iBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBiBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBiBBBB 
■■■■■■■BEBBBBBBEBB  BBBBBBBBBB  BBBBBBBBBB  BBBBBBBBBB  ■■■■■■■■■■  Hi 


IBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB 
IBBBBBBBBBBBBBBBBB BBBBBBBBBB BBBB 


jiBi»BiBlBBBiRBB*aiiiBBBBBBBBBlBBBffl9?';.'3iB^g®P«5^^^^^™ 

!g=jii”=i5sgsaigsaigii5!s:sii^i;is;5;i«5iii5;s5^!5HgBggBBg!!!gggHgg!!ggi!M 

;ggggggggggggggggggggggggggggt15888883B”8SB88388i ‘88888888*888888888885888888888883 


IBBBBBBBBBBBBBBBB 

IBBBBBBBBBBBBBHM 


■■■BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBri^BBBBBBBBBBBBBBBBkRBBRUBlBBBBBBflB 
HBBBBBSlBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBPWJBBBBBBBBBBBBBBBBBBBBB^BhiBBBBBB 
BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBHBBBBBBBBBSBbBKBBBBBB 

■SySSSSsS&&HSS3SSSSSSSSSSSSSSSSSSSSSSS8SSSSSSS!caSSSSSuM«SSSuSSSSS5"StSSSSSS 


IBBBBB  BBBBB£B£BB  BBBB 


BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBrjBa..RBBBBBBBBBBBBBBBBBBBBBBk"B^BBBBBB 

bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbpbbbbbbbbbbbbbbbbbbbbbbbbb^bbbbbb 


BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBRJBBB^BBBBBBBBBBBBBBBBBkBBBBSBBBBBBBB 
iBBBBBflBBBBBBBBBBBBBBBflBBflBBBBBBBBBBBflBBBBBBBB'JBBBLBBBBBBBBBBflBEflflBflBBBflE^a^BBBBftif 
IBBBBBBB  BBBBBBBBBB  BBBBBBBBfilBilBBBBSBBflBSBflRBBBVBBBKlBBBBBBB  BBBBBBBBBB  BBBBB^  B£BBBBB1 
BBBBBBBflBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBflriBBBB«.BBBBBiBBBB|BBflfliBBBfliBt'BBBB|BBH 


3il 


IBBBBBBBBBBBBBBBBBBBBBBBBBBBflflBBBBBBBBBBBBBBBFiBBBBB^BBBBBI 
IBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBriBBBBBlaBBR 


BBBB  BBBBP.tB^BB  BBBB 
IBBBBBBBBB^HgBBBBBI 


jaBBSSBBS8888888SSS88888S88S8888S8888SS88S888S888888iyS 

iBBBBByj m ■ : mi  ? ..  bsrbbbbssTBB' ws- zrsn. 


IBBBB 'VBflBB  J*BMBB  BBBI 


mm.  KBBBBBBBBBBBBBBBBf'lil  IB'  ■ BBR.BILQ'B.'^&I  i iu 
■BBBrjBBBBB  BBBBBBBBBB  BBBBBBBBBB  BBBBB'H^BB  £«BB 
BBBBBBBBBBBBBBBBBBflBBBBBBBBBBBBBBBBBBBflBBBBBBBBBB^B^BBBIkBI 


IBBBBBBBBBBBBB‘:-  JBBBBBBBBBE*!  H H mm 

BBBBBBHBBBBBB»:  IBBff  BBBBBiEi  aflBBBEBBBIESBBB 

88MjBBBBiammBI8!8BliiHBHHHI 

i i W 'S  T:  B 1 H^BBBB.% BBB  BBBBBBBBBB  BBBBBBBBBB  BBB  BBBBBBB  BBBBBBBBBB— ——B—B 

IBIBfllRI>BBBBI^HBHHHHHB|RHHHHMHB 

kBBBBBBBIBBBBBBK;.. 
iBBBi&SlKBB  13Ria&\ 


BBBBBBBBBB  BlBlRHHHHnMHHHHHHi 
■BBBBBBBBBB BBBBBBBBBB BBBBBBBBBB BBFBBBBBBB BBBBBBBBBB BBBBI 


IF4I 


BBBBBBB^BBSH^BB^iyBl 


IBBBB  BBliflfl?BNBBK!iBI 


IBB BBBBBB*CBBVBBBBBBBBBBBBBBBBBBBB BBBBBBBBBB BBBBBBBB 


«HflBBBBBBBBBBBF!*t'BflL*  BBBBBBBBBB  BBBBBBBBBB  BFiflBBBBBBBBBBBBBBBBBBBBBI 
HBBBBBBBBBBBBBLIBB ^BBBBBBBBBB BBBBBBBBBB BBBBBBBBBB BBBBBBBBBB BBBBI 


BBB  BBBBBBBBBB  BB^BBBB^Bfl^jaBI 
BBB  BBBBBBBBBB  BBCBBBB<.3BB^Bi 


■BBBBBB\BBS.RJn>BBBBBR 
IBBBBB  KBgflBMB^BB  BBB1 


PBBBBBBBB9  BBBBRlBBN  BBBBBBBBBB  BBBBBBBBBB  FiBBBBBBBBB  BBBBBBBBBB  BBBBBBBBBB  LiBBBBL.BNBB*RBBB 

|BBBBBBBB^BBBBT<BB  A BBBBBBBBBB  BBBBBBBBBB  FiBBBBBBBBBBBBBBBBBBBBBBREBBBtB^  3£»>SfeLsBw  BBftiZBE 
■BBBBBBBB  B^BBBBCBBt  BBBBBBBBBB  BBBBBBBBBB  BBBBBBBBBB  BBBBBBBBBB  BBBBBBBBSttcBBhiBB^BBBB^SBI 
IBBBBBBBBBBw«BBBBSBB<BBBBBBBBBBBBBBBBBBBriBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBgBBBEB^BBR>;RBB 
■■■■■■■■■■■■■■■■iRRSRBJlBRBSSBBflBBBflBBiaBHIflBflBBBRiHMMHflMBl 


IBBRflBRBBfl*'MRBBB>flB*'BBBBBBB 


BBBBBBBBBB  RRBBRiBBHHHHHHHHlH^HHHH 
IBBBBBBBB  B*BBBB?BB  ,▼  BBBBBBBBBB  BBBBBBBBFB  BBBBBBBBBB  BBBBBBBBBB  BBBBBBBBBB  BB^BBC'  BftBB  fcBBI 
IBBBBBBBBBBBBBBKBBVBBBBBBBBBBBBBBBBBBfJBBBBBBBBBBIBgBBBBBBBBBBaBBBBBaaBB.vBBstB^BB^BBff 


IBBBBBB^BBBC^Bfll'^BR 


IBBBBB  BE  >BB^B^BB^BI 


IBBBB  BHBBBB:«BB«  BBBBBBBBBB  BBBBBBBBBB  BBBBBBBBBB  BBBBBBBBBB  BBBBBBHHBHHHBHHMI 
HVBBBBrSBBBB^BBw  BBBBBBBBBBBBBBBBBfiBBBBBBBBRHiBBBBBBBBBBBB  BBBBBBBBBB  BBwBBkTBSBBBKBI 
IBBB>CBBB  B^BBBBK-BBr:  BBBBBBBBBB  BBBBBBBBBB  BBBBBBBBBB  BBBBBBBBBB  BBBBBBBBBB  BNBBBBCt'BB  J£*BB 


SBBBBJBBBBBBBBBSBB.T' BBBBBBBBBB  BBBBBBFBBB  BBBBBBBBBB  BBBBBBBBBB  BBBBBBBBBB  utlbBEB^Bi^BBEgLEi 

■bBI  ^B.V'BBBBBBEv'BL't'  BBBBBBBBBB  BHBBBBfiBBB  BBBiSffiglHBBB  BBBBBBH  ::HBBHBBflBflMBB 


"Bfl k^BI 


I^BNBfliSB^BBfeiBBBBBBBBBBBBBBBBBBriBflBflBBBBBBBBBBBBBBBflBflBBBISBBiRBBBBBBBrBBi^B^^BBkflBI 
BPkB^BB^BSBBBBB^ BBBBBBBBBB BBBBB'IBBBBBBBBBBBBBBBBBBBBBBBB BBBBBBBBBB BK  JMBBBSBBB^BR 
BBVil^Bi^BvBB^BB't  BBBBBBBBBB  BBBBFttBeSBB  BB«BSSi»iaBB  BBBBBBBBBB  EflBSBBIHBflBBHIflBBBflRHRRBBflM 


IBBBB BBSBB^BV^B «^BB 


IR^BBBBBBBBBwrBBLlBBBBBBBBBB  BBBBBBBBBB  BBBBBBBBBBaBUBBBBBBBBKiBBBBBBBflliB^BB^BiC.BBBBB'l 
~155BgBBBBiTBBBBABB.?BBBBBBflBBBBBBflB.BBflBBBBBBBBBBBBBBBBflflBBBBBBBBBBBBBBttB!lBBNBi»BflBBBB 

■IBBBBBBBB^BBBB^BBaBBBBBflBBBBBBBBB^HHIBROgBiaBBBHgiBBBBBBflBBIgBBBlIBHaffiiliiBBBBBBBSgBIBBBIi^l 
BBBBBBfl^BBBIlSBB^BBBBBBBBBBBBBBflBBflBBBHBRIHBBBBBBBflBBBBBBBBBBBBBBBBBBBBBBlLM^BBBBail 
■■■■■■■■L»Biil.BS^SBBBBBBBBBBIIBBBBMBB»EHEBBBBBBBBflBBflBBBBBBBBaBBBBBBBBBBBB.NBflaBBS 


IBIBBBBBBBBBBBBBBBBBBBBBB^BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB 


vBkNl 


I ■■■■■■■■■  B^BBBPwIBBlBflflBBBBBBlRIBBBBBIi.lflliiUk.BiaBBaCBa  BBBBBBBBBB  BBBBBBBBBB  ■EBBi  ^BBS«RIMil« 

EEEESHSEME^HS*BBBBBBBBBaBBBBBBB*,BaBa^B05a*B*BaBBBBBBBBBaBBB*iiBBBBBaBBBB*^B,i<ttaa,a«a 

l!E5!!55S!^!!!!±!!^aaaBBHHBBaBBBBBHBB>lllEi(iEl'',VN,KHiaBastiGBBaBBBBaBBaNBBaBBaiPBBIIB'','hsa!iHBK^ 

■5  S^BBflBBBBB  BBB||BBBBBa  BBBBBBBBklB  HSaaBMU  BBBiiaHan  MaBBiaKBB  aBBBac'^^aB  aaBB 
■■■■■■■■BBTBBBBOBBBBBBBBBBBBBBBBBBBBBBBBB>\BBBBBBBBBBBBBBBBBBBBBBBBBBBIIBBBIi.\'HNBBBBBa 
■■■■■■■■■■  aBBBB^BBBBBBBBBBBBBBBBBBBBBB.l  BBBBBBBBBB  BBBBBBBBBB  BBB^BBBBMBkBBflCC'B^iKBBBKB 

55555SS552!i5SBS^BBaBBBaBliaBBaBBiBBB!®,iBB5|i,Ba^MBB*!®Haa8®BBBBBBaBBaBBBBBBaBsBaB^B-rBaaBa,lt 

l5SSBBS5SBSSS5S£YSB5BBBBBBBBIiaBBBBBBBBBaBB^BBBBBBBBBBBBBBBBaBBBBBBBBBBBBBBBBBaaaBB! 

li5aBB5SBBBBBBBCBBBflBBBBBBBBBBBBBflBBBBB^BBBBBBBBBBBBBBBBBBBBBBBBB8SBBflBBfllBB^BBBBBBBK 


iBf  ;s 


B9P5BSSB5SBBB55S55BSS5BBBBBBBaBBBBBBBBBaaB^BBBBBBaBBBBBBBBBaBBBBBBBBBBBBBaB^B^^aBBBa 

B*  *BBaaalaaaa!l!ia!!I!B!IIII!!!BBBBBB3^£.l  gBHttgtBBBBaBBBBBaBBBBBBBBBEjBBBBB»,Sa»>BMlo 


i;gBBBBBBaBSBBBBiaiaBBBBBIi«aBBBBBBBBBRlBk’VBIiKaSSBB«HaRB*BBBSSBBBBRBBI!IBBaBBRJK^B*BI*-'  * 


!BBBBBaBBBllilllililllaalBBBBBBBBBBBBBl*.BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBCBBBBPf’ 

■■■■■■■IBB  BBBBBBBBBB  BIBBBBHHMMMMMniHIHflBHHHHHMfllBflBM 


■■■■■■■■■■■■■■■■■BBBBBBBBBBBBBBBBaRBBRH BBBBBBBBBB BBBBBBBRRS BBBBBBBBBB BBBBBBBBBB BBS 
EBBBBBBBB  BBBBBBBBBB  BBBBBBBBBB  BBBBBBBBBB  BBB'rlflBBBBBBBBBBBBBBB  BBBBBBBBBB  aIBBBBBBi',BBBBBU 


555555SSS5SSES5S5S!S555SS5!B5':iBBBBBBBBaaBBBBBBBBB*BBBBBBBBKaBBBBBBBBBMBBBBBB£flBBi 

■ilillllllilllllHBBBBBBBBBBBBJBBBBBBBBBlBBBBBBBBB.lBBBBBBBBBJBBBBBBBBBBBBliBBBvsBBBI 


■■■■■■■■■■■■■■■■■■■ BBBBBBBBBfc JBBBBBBBBb  FBBBBBBBBft.  SBBBBBBBBk  'iBBPBBBBBB BBBBBBBBBB K 


iliiilililllBBllBBBBBBBBBBBBBB 


.BBBBBBBBB BBBBBBBBBB BBBBBBBBBB 

■■■■■■■■■■■■■■HHMHBHPBbbib 


BBBBBBBBBBBBBBBBBBBBBBBBBBI 


IBB 


IBBBBBBBI 


IBBBBBBBI 


■BR^H^HdBB  BBBBBBBBBB  BBBBBBBBBB  BBBBBBBBBB  B 

IBBBbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbm 

BBBBBBBBB  BBBBBBBBBB  BBBBBBBBBB  ■■BBBBBBBBBBBBEIBEIERM 


IBBBBBBBBBBBBI 


IBBBI 


IBBI 


IBBBBBBBI 


IBBBBBBBBBBBBBBBBI 
■BBBB  BBBBBBBBBB  Bl 
IBBBB BBBBBBBBBB B 


IBBBBBBBI 


lil  HI 


IBBBBBI 


IIIR1I 


18 


■■ 


ibbbbi 


IBBBBBI 


mi 

in 


fs:::§3£:£:3ii 

ammmm 


■■■i 


IBilHBBBBBBRSSfiesgB! 


■■■■I 


IBBBBI 


IBBBBBBBB$;ii»31BaBBBSaBHBBBIKBRBBBai  - 
iBBBBBBEBEBaEBEBBBBBBaaBBBBBBEk 

■■■■■■  HIRIBR  BIS  a tSM; 


BfBHBglssg^SssssssssBasssssssszssaii^asssssssassassassaasssssg 


■BBBBB£B^aBBBBBBI 
IBBBBBKTBlL'BflBBBBBI 
|B!*BBBBBBBBB  BBBBB! 


BBBBBBflBBBEWSBBBBBBBBBBBBBBBBBBBBflBBBBI.BBBBBlBEEEEEESESSESESSSESSEEEEEE.^ESili**1 


BBBBBBBBBt*BifcBBBBBBBBBBBBBBBBBBBBBBBBBIlBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBfcB^ilBBM§!«fc?! 

iBBBBBBBBBBSSRBBBBBBBBBBBBBBBBBBBBBBBBlBBIIBBJiBBBflBBBflBBBBBBBBBBBflBBBBBBBBBanw'tlRB^^S^: 

E3ss&sss£!£issi2&^ 


BBBBB  BBBBBBBBBBBBflBBBBBBBBflBBBBBEPPBB  IBBBBBBB  BBBBBBBBBB  BBBBBBBBBBBBBBHSB>''3BBBBBB 
BBBBBBBBBBBBBBBBBBBBBBBBRBBBBBBBfcBBBBaBBBBBBBBBBBBBBBBBBBBBBBBBBBIlBBBBPBBBBBBBBB 


IBBBBBBB  BBBBBBBBBB  BBBBBBBBBB  BBBBBBBBBB  BBBBBBBBBB  BBBBBBBBBB  BBBBBBBBBB  BBBBBi(]BrrflB  BB^BB 


BBBBBBI 

BBBBBBI 


IK  I 
IBI 


BBBBUBBBBBBBBBBBBBBBBBBBBBBBBBB! 


BB  BfIBBBBBBBB  BBBBBBBBBB  BBBBBBBB! 


BB BBBBB 

IBBBBBBh 


■KKTiBBBBAV  El 

Bw BBBB  BBBkEI 


IBBBBB BBBBBBBBBB 
IBBBBBBBBBBSX.BBB 
IBBBBB  BBBBBBBBBB 


BBSS 


SlBBflBBBBBBBIHBBBBBBBl  JBBBBBBflBBBBBBBBBBflBK3ISRBBSrBBBBB«BB\9  r- 
lsaBBRflSBlflBBBBBaBnVBBB«aRSKfaSBBBBBBBBBBB@SBBBBBBBBB«.BBVBSh»gsaiBKS' 
PHMHHMBBBBBBBBBBBBBBBBBBBriBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBSV'BEIXNBBBBflSBBi 
BBBBBL^BBB  BBBBBBBBBB!  BBBBBBBBB’I  BBBBBBBBBB  BBBBBBBBBB  BBBBBBBBBB  LBBBB>^Bt>BBBB^BB 
BBBBBBBBBi>SBB!(  BBBBBBBBBB  BBBBBBBBBB  BBBBBBBBBB  BBBBBBBBBB  BBBBBBBBBBBBSBB^BJlBHBBgaiB1 
BBB  BBBBBPtyBB*  BBBBBBBBBB  BBBBBBBBNB  BBBBBBSIRBB  BBBBBBBBBIS  BBBBBBBBBB  BK'BBfcB JBK  BB**?B 

BBBBBBBKI'IBB.^  BBBBBBBBBB  BBBBBBBBr4B  BBBBBBBBBB  BBBBBBBBBB  BBBBBBBBBB  BBKBB'flk^BS'BB5  BB 
Bb  BBBBBBISBB>BBBBBBBBBB  BBBBBBBBBB  BBBBBBBWBM  BBBBBBBBBB  KBiBBEBgSHBBBB'^BBvPfrg%  BE*?.  £*B 
BBBB3.BBBBBBB  5 BBBBBBBBBEEEEEEEEFiBM  BBBBBBBBBB  BBBBBBBBBB  BBBBBBBBBB  BBCBB"-  i^KBMBB 


I BVBBBB.VBBT  BBBBBBBBBkl 
I B^BBBBtMBB^ti  BBBBBBBBBB 


IBBBBBBB  FCBBBBCBB^.’  Bl 

IbBBBBIBE1  EBBBINBB  Tll 


■ ljm mmmmmm . ira 

MlBBBBBBBBBBBBBBBBBBBBBBBBBBflBBBBBBBfe>BB\L'lflBBBBfe£B 
EEEEEEir  BBB  BBBBBBBBBB  BBBBBBBBBB BBBBBBBBBB  BPBflflkLii  ABB  BB  BAB 
^EEEEE-iBBB  BBBBBBBBBB  BBBBBBBBBB  BBBBBBBBBBBB^'BBBB%BBflB^i  B 
■BBBHBBBBB BBBBBBBBBB BBBBBBBBBB BBBBBBBBBB MB^BB^ByBBBB^BB 


IBBBBBBBBKBBBBJ BBA BBBBBBBBBB BEE EEF.BBBB BBBBBBBBBB BBBBBBBBBBBBBBBBBBBBBB^BBBgBBBBBJ BB 

BBBBBBBBBBEBfl?NB«BBBBBBBBlBBLHHHHHHHHHHHHHHHHHMHi 


■■■— —iBBBB  BBBBBBBBBB  BBBBBBBBBB  BBBBBBBBBB  Br>BB3BgBBBlg«B 

IBBP  BBBBB  JIBBBBXBB*  BBBBBBBBBB 
|BBBiy BBC  KVBBBB^.BB *;  KSSi2?3i  BF^KS  ; 

iiMBBBBLiiiiTiiNBiiBBBBBaBBBiiiHMMHMMMMMMMMMBHHH 

IBIt^BT^BBBBBBB^Bri^  BBBBBBBBBB  BBBr:iBBBBBB  BBBBBBBBBB  BBBBBBBBBB  BBBBBBBBBB  BB^BB^BBEl 
IBRiiSBKBBlB.lSBIkHBBl  BBBBBBBBBB  BBBBBBBBBB  BBBBBK.BBBB  BBBBBBBBBB  BBBBBBBBBB  BBkNBMSBBBfl  BBBBB 

gBUrB^BB«BwtB»9:BBBflBBBBflBBBflBBEBVSBflBBBBBflB;»'?:x:^’JK&£/^Brr:BF‘£2Z;^flBBBBBBfc2'S^BBBBBBB 
IBBidBSBflXBiVBBBBB  A BBBBBlBBBBBBFiBNBBBBRBBBBBBKiBBaBIiBBBaBEaB  BBBBBBBBBB  BB.NBBj^K'dBB  BBBBB 
IBMik'B^BBABTVBBBBB-c  BBBBBBBBBBBBBBK'BBBBB  BBBBBBBBBB  BBBBBBBBBB  BBBBBBBBBBBB  SBBT'aiZikl  BBBBB 


rBBBBB BBBBBBBBBB BBBBBBBBBBBBBBBBBBBBBB^BB^B^BBBBB^B 
IBBBBB BBBBBBBBBB BBBBBBBBBB BBBBBBBBBB BBBBBBBBBB Bfl  ®^B 
IBBBBB BBBBBBBBBB BBBBBBBBBB BBBBBBBBBB BBIBB^BTBBBBK^B 

MMBBBHBMMMBMHMBnHKBBBBBBMBBMBWBI 

US 

r 


§SlBBMB3'BBS!BKBB>BBkLi  BBBBBBBBBB  BTiBBBABBBB  BBBBBBBBBB  BBBBBBBBBB  BBBBBBBBBB  MB^BB> 
IBBliiSBi'SBBRiByBBXBSi^  BBBBBBBBBB  BBBBBBBBBB  BBBBBBBBBB  BBBBBBBBBB  BBBBBBBBBBBBXBBy 
iBBBEBVBB:  BBBB.'.BB^BBBBBBaBBBaBBBBaiBMgaqgBBBgBBgliBBgBBBgWKBRffiaBy^  ^BBBB^B^^ 


syiSK8sssi:s:: 


IBBF^BEB BBBBBB>BBrTBBBBBBBBBBBBBBBBk1BBBBi#aBBBBBBB BBBBBBBBBB BBBBBBB'BBBflBJBB  ^QABnBBBBB 
IBBliiS'BBBBBBBBBXBBXBBBBBBBBBBBBBBBBB'BBBBBg'BBBBBBB  BBBBBBBBBB  BBBBBBBIBBBBPrBB^B’NB^BBBBl 


BBBBBBBBBB  BQBBBBfl ABB  BBB BS^CBBBB  BBBBBBBBBB  BBBBBBBBBB  BBWflBc'B^^i  kJXBBB 
IBBBBBBBBgBBBBjBBg  BBBBBBBBBBBBBBBBBi^BB  BBBBBBBBBB  BBBBBBBBBB  BBBBBBBBBB  BBBBB  JBlLBgBBBll 


BBgBBBBB^BBB^BB'SBBflBBflBBBBBBBBBBBBBBBBsSflBBBBBBI 


h--Jsss5s^sss®*S5®*®®B*"*8S®»*®BaRRBB?BS5SSS®SSS5si5S*BSB 

IBBBBBBBB^BBBBaBBBBBBBBBBBBBBBBBBBBBB'BBBiMBBBBBBBBBBBBBBBBBBBBBiiBiiiiBBBWSBSll^BBBBB^ 


■■T'BBBk'  BBBBB 
BB^BkVX^BBBflB! 


llllllBl^llBT^BBi;  BBBBBBBBBB  BBBBBBBBB  A BWEBBBBBBB  BBBBBBBBBB  BEEEEBBBEBBEEBB?KS1B  Hill! 
llllllll^lIll^liSlBBBBBBBBBBBBRBBBBBVBB^BBBBBBBBBBBBBBBBBBBHHMMMaHWMMliailfltt 


[■■■■■■■  ■T'BBBBBBBK  BBB  BBBBBBI  BBBBBBBBBB  BIHIbIH^H 
MBBEEEB BXBEBE^BBBBEBBEEBBBB BBBBBBBBBB HCBBBE 


■SffiBBBBBBBBBBBBBkB^B  S BBBBB 
B BBBBBBBBBB  BBBBBBB^lBC!  Hill1 


bbbebbbbbpbbbibbbibmbrmbhhbhbbbbbbb 
BBBBBBBBB BBBBBBBBBB BBBBBJBJBtflg 
BBBBBBBBB  BBBBBHBMaaHMHMaaMH 


388S8SSE«8SiaS8S8i88SSg888S8Sg8I8!liA.^^H 

iiSiSiiSiSSgvSiiiasiSKKSiSiiiiiiii^rKSiiHHgggHgigggHgSHggHHHHHggB 


BHBBB  BBBBBBBBBB  BBBBB<?fl^a  A BBBBBI 
■BBBBBBBBBBBBBBBBBIr'NB<3i^lillli 


SBBB  BBBBBBiSiBBB  HiSiBISS  WU;#*  <£  b ■;;« 

BiliBBlIgBlIBUH  WBIBBBibBBBBBBBBBBBmiBBBBBaBBBBBBBBBBBBBBBBBIiBBBBBBBaB<JBcBi 

— — — — — — BB— — ■ — | — — — — iBBBSBgaB  WBBMBl^.  BBBBB1 


[■■■■■■■■■■■■■■■BBBBBBBBBBBBBBBBBBBBBBBBBrjBBBflaRBBBBBBBBBBBBBBBBBBBBaBBBBBB^BJ'BiBBB 
■■■■■■■■■■■■■■■BB BBBBBBBBBB HBBBBBBBBBlIBBBBBBBBB  ABBBBBBBBB*BBBBBBBBBItBBBBflBUBS BBBBB 

EEEEEE2EEEEEEEEE5ESSEBBBBBBkJB*BBBBBBBJBBBBB®®*aJI®*BBBBBB*'flBB**B®'1Ba®B*SIB®)PBB^22i2El 

!ESSEE2S2ESSSSSSEE212EllllB^BBBBBHBkABBBBBaBBft.AflBBBBBBBrABBBBBBSBBBBBBBBB«a^BBBBS 


EEEEE2EEEEEEEEE2EEEEEEEEBBBBBBBBBBBBBBBBBBBBBBB0BBBBBBBB®BBBBBBBBaBBHBBBB‘ijB£222£2 

^2EEE2EEEEEEiES2BEB2BEEEEEBBBBB^i^r^a*^*B?sr',:r'BB^^jrr-:/'WiFr^r‘*^*^BBBBBBBBE222222 

■■■■■■■■SSSSBSS2ESSESSSBBB ■■■■■■■■« ■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■22222S 
■1IIII ElEES^ifiElElEElEllBB !■■■■■■■■■■■■■■■■■■■ ■■■■■■■■■■■■■■■■■■■■■■■■■■!!!! 1EESS 


IEEEEEE!EEEEEEEEE! !!!!!!!!■■ ■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■»£■■■■■■ ■■■■■■■!»! aHBKB 


IBBBI 


{ 


f 


t 


104. 


In  order  to  illustrate  the  method  of  estimating  and  the  relative 
economy  of  various  systems  of  road  building,  a typical  estimate  of  the  cost  of 
operation  will  be  shown.  No  attempt  will  be  made  to  consider  overhead  charges, 
cost  of  material,  workmen's  compensation  and  accident  insurance,  public  liability 
insurance,  contractors  bond,  etc.  A road  8 miles  long  with  the  unloading  point 
opposite  the  center  and  1 mile  away, will  be  considered.  The  type  of  pavement  will 
be  concrete,  18  feet  wide,  7-l/3  inches  in  average  thickness,  and  of  a 1-2-3  mixture* 
The  output  of  road  will  be  assumed  to  be  l-l/4  miles  per  month,under  normal  con- 
ditions, with  a 14-B  mixer.  At  this  rate  the  concrete  should  be  placed  in  about 
6-1/2  months  or  130  working  days. 

A traction  crane  costing  $10,000, equipped  with  a 35  foot  boom  and  a 
3/4  yard  clam  shell  bucket,  will  be  used  for  unloading  material.  The  tunnel  system 
of  storage  will  be  used  for  the  light  railway  plant,  and  a 200  cubic  yard  bin 
and  stock  piles  for  the  motor  truck, and  combined  light  railway  and  motor  truck, 
plants.  Detailed  drawings  of  the  tunnel  and  bin  will  be  found  in  the  appendix. 

A 14-E  paving  mixer  operating  at  a rate  of  400  feet  of  road  per  10  hour 
day,  will  require  the  following  quantity  of  material: 

285  bbls.  cement  or  54  tons  or  l-l/2  cars. 

85  cu.yds.  sand  or  127  tons  or  2-l/2  cars 

127  cu.yds. stone  or  172  tons  or  5-1/2  cars 

7-1/2  cars. 

A crane  of  the  type  we  have  assumed  is  capable  of  unloading  from  10  to 
12  cars  of  material  per  10  ho  in*  day,  so  it  has  ample  capacity  for  the  purpose  we 
have  in  mind.  The  cement  will  be  shipped  in  bulk  in  open  top  cars,  and  will  be 
unloaded  into  a bin  in  the  same  manner  as  sand  and  stone. 


The  plant  charges, consisting  of  interest,  depreciation,  repair,  etc. 
are  in  accordance  with  the  "Guide  to  Estimating  Construction  Equipment  Expense" 
recommended  by  The  Committee  on  Methods  of  the  Associated  General  Contractors. 

No  plant  charges  or  fuel  charges  are  made  for  rented  equipment,  as  these  charges 
are  taken  care  of  by  the  owner  of  the  equipment  in  his  rental. 

COST  OF  UNLOADING  AND  PROPORTIONING  MATERIAL 


1 crane  operator  7 months  @ $180.00 
1 crane  fireman  7 months  <§  $144.00 

1 bucket  man  140  days  @ 4.00 

2 clean  up  men  130  days  @ 4.00 

2 bin  or  tunnel  men  130  days  4.00 
1 water  boy  130  days  @ 2.00 

coal  and  oil  140  days  @ 8.00 

Labor  and  Fual 


$1,260.00 

1,008.00 

560.00 
1,040.00 

1.040.00 

260.00 

1.120.00 
$6,288.00 


Plant  charge  on  crane  @ 34-g $ 3,450.00 
Plant  charge  on  31  tunnel  traps  @ 37 $ 270.00 
Plant  charge  on  clam  shell  bucket  @ 50$  350.00 
Plant  charge  on  250  feet  of  tunnel  @ 67$  1,675.00 
Plant  charge  on  1500  bbl.  bulk  cement  bin  @ 67$  1.675.00 


Plant  charges  $7,420.00 


J 


105 


Dismantle  tunnel,  25,200  feet  of  lumber,  @ $5*00  $ 126.00 
Dismantle  bin,  16,000  feet  of  lumber,  @ $5,00  80.00 
Load  41,200  feet  lumber,  board  measure,  @ $2.00  82.00 
Freight  on  lumber,  24$  cwt.(ship  150  mi*)  331.00 
Freight  on  crane,  24$  cwt.,  40,000#  96.00 
Load  and  unload  crane  @ $2.00  per  ton  40.00 
Rental  of  ground,  about  1 acre  200.00 
Back  fill  tunnel  trench  and  clean  up  300.00 
Railroad  charge,  installing  switch  points  and  frog  1,200.00 
700*  siding  after  rebate  for  rails  and  ties  1,400.00 


$3,855.00 


Total  cost  of  unloading  and  proportioning  material  $17,563.00 

Cost  per  ton,  unloading  and  proportioning  material  $ 0.47 

If  a 200  cubic  yard  bin  is  used  in  place  of  a tunnel,  it  would  cost 
about  $1,500.00.  Considering  the  greater  amount  of  rehandling  of  material 
necessitated  by  a bin,  the  final  cost  of  unloading  and  proportioning  material  would 
be  just  about  the  same  as  for  the  tunnel  system  shown  above. 

If  the  5 ton  motor  truck  method  of  hauling  material  is  used  and  material 
is  dumped  on  the  subgrade,  a speed  of  6 miles  per  hour  loaded  and  10  miles  per  hour 
empty  is  a good  average  over  fairly  good  earth  road.  At  this  rate,  allowing  5 
minutes  for  loading  and  10  minutes  for  dumping  and  getting  away,  a truck  should 
make  the  round  trip  of  6 miles  on  the  average  haul  in  63  minutes.  This  is  equiva- 
lent to  9 round  trips  per  10  hour  day.  The  sand  and  stone  required  on  this  job 
amounts  to  6,318  - 5 ton  loads,  and  inasmuch  as  1 truck  shnuld  average  9 trips 
per  day,  702  truck  days  are  required  for  hauling  sand  and  stone.  To  perform  this 
amount  of  work  in  130  days,  6 trucks  must  be  assigned  to  the  task.  To  haul  30,166 
barrels  of  cement  will  require  1,134  - 5 ton  loads.  At  a speed  of  6 and  10  miles 
per  hour  for  loaded  and  empty  trucks  respectively, with  an  allowance  of  20  minutes 
for  loading  and  20  minutes  for  unloading  and  piling  a 26  barrel  load  of  cement, 
the  round  trip  on  the  average  haul  of  3 miles  should  be  performed  in  88  minutes. 
This  is  at  the  rate  of  7 per  10  hour  day,  requiring  162  truck  days  of  work  to  haul 
1,134  loads  of  cement.  The  services  of  l-l/4  trucks  are  necessary  to  perform  this 
amount  of  work  in  130  days*  and  inasmuch  as  cement  cannot  be  stored  on  the  road  in 
any  considerable  quantity, it  is  necessary  to  assign  2 trucks  to  haul  cement.  A 
total  of  8 trucks  are,  therefore,  necessary  with  this  system. 

When  a 5 ton  truck  with  a subdivided  dump  body  is  used  to  charge  the 
mixer  direct,  the  speeds  of  6 and  10  miles  per  hour  for  loaded  and  empty  trucks, 
respectively, will  apply.  At  this  rate,  with  an  allowance  of  12  minutes  for  dumping 
4 batches  into  the  skip  of  the  mixer  and  getting  away,  a truck  will  make  a round 
trip  on  the  average  haul  of  3 miles  in  65  minutes.  This  is  at  the  rate  of  9 trips 
per  10  hour  day,  enabling  each  truck  to  deliver  36  batches  to  the  mixer.  To 
deliver  300  batches  per  day  will  require  the  services  of  9 trucks. 


A Ford  truck, carrying  complete  materials  for  1-4  bag  batch  of  concrete, 
will  average  a speed  of  about  12  miles  per  hour  loaded  and  enpty.  At  this  rate, 
allowing  3 minutes  for  loading,  filling  radiator,  etc.  and  2 minutes  for  dumping 
into  the  mixer,  35  minutes  are  required  pa*  round  trip  on  the  average  haul  of  3 
miles.  This  is  at  the  rate  of  17  trips  per  10  hour  day,  so  that  18  trucks  are 
needed  to  deliver  300  batches  to  the  mixer.  Experience  indicates  that  a surplus 
of  about  one- third  of  the  number  of  trucks  required  to  supply  the  mixer  must  be 


106. 


provided  in  a light  truck  plant,  "because  of  the  severe  operating  conditions.  A 
set  of  oversized  tires  should  not  "be  counted  on  to  give  much  more  than  4,000  miles 
of  service,  nor  a gallon  of  gasolene  much  more  than  about  8 miles  of  travel. 

In  the  combined  light  railway  and  motor  truck  plant,  the  truck  haul 
varies  from  a minimum  of  1 mile  to  a maximum  of  3-1/2  miles.  Over  the  1 mile  of 
unimproved  road  between  the  material  yard  and  the  job,  a speed  of  6 miles  per  hour 
loaded  and  10  miles  per  hour  empty  is  a fair  average  for  5 ton  trucks.  A speed  of 
10  miles  per  hour  both  loaded  and  empty  should  be  maintained  over  the  finished 
pavement.  Allowing  5 minutes  for  loading  and  10  minutes  for  transferring  4 batch 
boxes,  a truck  will  require  31  minutes  per  round  trip  on  the  minimum  haul  of  1 
mile.  This  is  at  the  rate  of  19  trips  per  10  hour  day,  enabling  each  truck  to 
deliver  76  batches.  Four  trucks  will  easily  deliver  300  batches  to  the  light  rail- 
way on  tlie  1 mile  haul.  On  the  maximum  haul  of  3-1/2  miles,  a round  trip  will 
require  61  minutes.  This  is  at  the  rate  of  10  trips  per  10  hour  day,  enabling 
each  truck  to  deliver  40  batches.  The  services  of  8 trucks  are  required  to  deliver 
300  batches  to  the  transfer  point  on  the  maximum  haul.  An  average  of  6 trucks 
will  be  needed  thruout  the  job. 

At  a speed  of  6 miles  per  hour,  allowing  5 minutes  for  switching  at  the 
mixer  and  5 minutes  at  the  material  yard,  a locomotive  will  make  a round  trip  on 
a 3.75  mile  haul,  three-fourths  of  the  maximum,  in  85  minutes.  With  a 7 car  train 
carrying  14  batches,  3 locomotives  and  5 trains  are  needed  to  supply  300  batches 
to  the  mixer. 

The  haulage  equipment  required  for  each  plan  of  operation,  assuming 
trucks  are  rented  for  the  combined  light  railway  and  motor  truck  plant,  is  as 
foil ows: 


COMPLETE 

COMBINED 

5 TON 

TRUCK 

FORD 

RAILWAY 

SYSTEM 

HAND  CHARGE 

DIRECT  CHARGE 

TRUCK 

Track,  5.25  mi 

.$33,171  1 

.5 

mi.  $9,478 

T.T... 



l/2  turnout,  14 

2,100 

4 

600 

| 

Curved  sec.  25, 

349 

10 

139 



Locomotives,  3 

13,800 

1 

4,600 



Cars , 35 

4,375 

24 

3,000 

f 

Batch  boxes,  70 

4,984 

88 

6,266 

Flat  Cars,  2 

830 

1 

415 

Trans,  derrick 

1 

1,500 

Motor  trucks 

6 

(rented) 

8-  $48,000 

9-  $54,000 

24-$24,000 

$59,609 

$25,998 

$48,000 

$54,000 

$25,000 

The  cost 

of  hauling 

on  this  job  should  be  about 

as  follows: 

COMPLETE 

COMBINED 

5 TON  TRUCK 

FORD 

RAILWAY 

SYSTEM 

HAND  CHARGE 

DIRECT  CHARGE 

TRUCK 

Loco . operators , 

7 mo.  @ $120.00 

$2,520 

$ 840 

Train  men. 

130  da.  @ $4.00 

1,560 

520 



Gas  & oil  for  loco 

• 

140  da.  @ $5.00 

2,100 

700 



Gas  & oil  for  trucks 

S 

140  da.  @ $5.00 

$5,600 

$6,300 

$12,600 

1 


107. 


COMPLETE:  COMBINED  5 TON  TRUCK  FORD 

KilimY  SYSTEM  HAND  CHARGE  DIRECT  CHARGE  IRUCK 

Truck  drivers, 

140  da.  @ #5.00  #5,600  #6,300  #12,600 

Trans.  Derrick  Men 

130  da.  @ $4.00  $1,560  

Lay  & remove  track, 

@ $200.00  per  mi.  $2,400  2,500  

Track  men, 

130  da.  @ #4.00  1,560  1,040  

Turntable  men, 

130  da.  @ #4.00  1,040 

Radiator  man, 

130  da.  @ #4.00  520 


Labor  and  Fuel  $10,040  $7,160  $11,200  $12,600  $26,760 

Rental  of  trucks, 

140  da.  @ $40.00  33,600  

Plant  Charge 

Track,  @ 30|%  10,864  3,116  

Locomotives,  @5 2$  7,176  2,392  ......  ...... 

Cars,  @ 34$  1,770  1,161  

Batch  Boxes,  @34#  1,695  2,130  ......  

Trans,  derrick  @ 33$  500  

5 ton  trucks,  @ 75$  ......  $36,000  $40,500  ••*... 

Ford  trucks,  @ 81$  ......  ......  $19,440 

$21,505  $9,299  $36,000  $40,500  $19,440 

Load  & unload  equip. 

@ $4.00  per  ton  770  266  •••.••  

Freight,  ship  150  mi. 

@ $0.44  per  cwt.  3,390  1,172  

Gas  & oil, 

moving  150  mi.  ..••••  105  118  132 

Tires,  move  150  mi. 

® #0.07  84  95  

Tires,  move  150  mi. 

® $0.03  108 

Truck  drivers, 

moving  150  mi.  130  147  240 

License  fee, 

@ $50.00  400  450  

License  fee, 

@ $20.00  480 

Tires,  7,000  mi. 

© $0.07  3,930  4,410  

Tires,  13,260  mi. 

@ $0.03  7,160 

Complete  insurance  3,200  3,600  1,800 


$4,160  $1,438  #7,829  $8,820  $9,920 


t 


"~s 


108. 


COMPLETE 

RAILWAY 

COMBINED 

SYSTEM 

5 TON  TRUCK 

HAND  CHARGE  DIRECT  CHARGE 

FORD 

TRUCK 

Cost  of  operation, 
labor,  fuel,  & plant 

$34,279 

$50,470 

$55,029 

$61,920 

$56,480 

Cost 

per  ton  mile 

$ 0.31 

$ 0.45 

$ 0.49 

$ 0.55 

$ 0.50 

If  trucks  are  rented  for  the  5 ton  direct  charging  system  at  $40.00  per 
day,  the  cost  would  "be  $50,400  for  140  days.  The  cost  per  ton  mile  would  be  $0.45 

In  the  foregoing  no  allowance  is  made  for  fuel  and  oil,  drivers,  or 
plant  charges  for  motor  trucks  on  the  combined  light  railway  and  truck  system, 
because  the  rental  charge  includes  all  of  these  items. 

The  daily  cost  per  5 ton  truck  when  material  is  dumped  on  the  subgrade 
is  $48.00  per  truck,  based  upon  140  working  days.  This  illustrates  the  statement 
previously  made  that  contractors  can  generally  rent  trucks  for  less  than  the  cost 
of  operating  their  own  trucks.  The  comparatively  short  working  season  in  highway 
construction,  is  responsible  for  this  condition. 

The  cost  of  mixing  and  placing  concrete,  should  be  approximately  as 

follows: 


EQUIPMENT  REQUIRED 


1 14-E  paving  mixer 

$ 7,925 

1 10-ton  roller 

4,000 

1 finishing  machine 

1,800 

1 subgrader 

600 

2000’  - 6”  steel  form  @ $0,912 

1,824 

1 double  unit  pump 

1,500 

10,560*  - 2”  wrought  iron  pipe  @ $0.32 

3,379 

132  tees,  @$0.36  (80-ft.  apart) 

48 

8 gate  valves,  @ $4.20 

34 

600  sq.yds.  tarpaulin,  @ $1.08 

648 

$21,758 


The  concrete  mixing  and  placing  equipment  shown  above  is  for  a complete 
railway  or  a combined  light  railway  and  motor  truck  plant.  When  material  is 
dumped  on  the  subgrade  or  the  mixer  is  charged  direct  from  motor  trucks,  the  sub- 
grader should  be  omitted.  An  allowance  of  $100.00  for  wheelbarrows  and  shovels 
should  be  made  when  material  is  dumped  on  the  subgrade. 

LABOR  AND  FUEL 


Mixer  operator, 

7 months,  @ $180.00 
Mixer  fireman, 

7 months,  @ $144.00 


COMPLETE  OR  5 TON  TRUCK 

COMBINED  KWY.  HAND  CHARGE  DIRECT  CHARGE 


1,260 

1,008 


1,260 

1,008 


1,260 

1,008 


FORD 

TRUCK 


1,260 

1,008 


s 


T 


t 


109 


COMPLETE  OR 

5 TON 

TRUCK 

FORD 

Finishing  Mach,  operator. 

COMBINED  RWY. 

HAND  CHARGE 

DIRECT  CHARGE 

TRUCK 

7 months , @ $144.00 
Pump  Operator, 

$ 1,008 

$ 1,008 

$ 1,008 

$ 1,008 

7 months,  @ $144.00 
Roller  Operator, 

1,008 

1,008 

1,008 

1,008 

7 months,  @ $180.00 
Head  form  setter. 

1,260 

1,260 

1,260 

1,260 

130  da.  @ $5.00 
Form  setter  helpers,  (2) 

650 

650 

650 

650 

130  da.  6 $4.00 
Concrete  spreaders,  (3), 

1,040 

1,040 

1,040 

1,040 

130  da.  @ $4.00 
Charging  mixer. 

1,560 

1,560 

1,560 

1,560 

130  da.  @ $4.00 
Curing  concrete,  (4), 

1,560 

8,840 

1,040 

1,040 

130  da.  @ $4.00 
Trimming  subgrade. 

2,080 

2,080 

2,080 

2,080 

130  da.  @ $4.00 
Pipe  me$. 

1,040 

6,240 

6,240 

6,240 

130  da.  @ $4.00 

520 

520 

520 

520 

Fuel  for  mixer. 


130  da.  @ $5.00 

650 

650 

650 

650 

Fuel  for  roller. 

130  da.  @ $5.00 

650 

650 

650 

650 

Gas  & oil,  finish,  mach. 

130  da.  @ $1.50 

195 

195 

195 

195 

Gas  for  pump, 

130  da.  @ $2.00 

260 

260 

260 

260 

Lay  & remove  pipe,  (10  mi.) 

@ $100.00  per  mile 

1,000 

1,000 

1,000 

1,000 

Water  boy, 

130  da.  & $2.00 

260 

260 

260 

260 

Sub- foreman  on  subgrade. 

130  da.  @ $6.00 

780 

780 

780 

Foreman, 

7 months,  @ $200.00 

1.400 

1.400 

1.400 

1.400 

Total,  labor  & fuel 

$18,409 

$31,669 

$23,219 

$23,219 

Plant  charge, mixer  @ 4 2$ 

3,328 

3,328 

3,328 

3,328 

" " , finisher  @ 52$ 

936 

936 

936 

936 

" '*  , subgrader&  42$ 

252 

" " , forms  @ 87$ 

1,587 

1,587 

1,587 

1,587 

" " ,pump  @ 35$ 

525 

525 

525 

525 

" '*  .pipe  @ 46$ 

1,602 

1,602 

1,602 

1,602 

" " , tarpaulin@100$ 

648 

648 

648 

648 

" ” , barrows  100$ 

100 

" '•  .roller  @ 25$ 

1.000 

1.000 

1.000 

1.000 

$ 9,878 

$ 9,726 

$ 9,626 

$ 9,626 

no* 


COMPLETE  OR 

5 TON 

TRUCK 

FORD 

COMBINED  RWT. 

HAND  CHARGE 

DIRECT  CHARGE 

TRUCK 

10$  material  loss, 

@ $3*00  cu.yd* 

$ 6,720 

Extra  concrete,  inaccurate 
subgrade,  @ $20  cu*yd.  * 

6,000 

$6,000 

6,000 

Load  & unload  56  tons. 

@ $2.00 

112 

112 

112 

112 

Freight  on  56  tons. 

@ $0.44  cwt. 

493 

493 

493 

493 

$ 605 

$13,325 

$6,605 

$6,605 

Total,  mixing  & placing; 

labor,  fuel  & plant 

$28,892. 

$54,720 

$39,450 

$39,450 

Cost  per  square  yard 

$ 0.34 

$ 0 • 64 

$ 0.46 

$ 0.46 

The  cost  show  in  the  foregoing  table  is  by  no  means  the  final  cost, 
as  no  allowance  has  yet  been  made  for  overhead,  bond,  workmen's  compensation, 
public  liability,  contingencies,  profit,  etc*  After  all  these  factors  have  been 
properly  considered,  the  allowance  for  profit  being  15  per  cent  to  20  per  cent, 
the  bid  price, including  material, should  be  about  35  per  cent  to  40  per  cent  in 
excess  of  the  estimated  cost  of  labor  and  material.  In  other  words  after  the 
cost  of  labor  and  material  has  been  estimated,  the  factors  of  contractors  bond, 
workmen’s  compensation,  overhead,  profit,  profit,  etc*  will  increase  the  cost  by 
approximately  35  to  40  per  cent.  A short  cut  method  of  quickly  estimating  the 
bid  price  after  the  cost  of  material  and  labor  has  been  estimated,  is  to  add  35 
to  40  per  cent  to  the  latter  cost.  The  percentage  to  be  added  to  the  estimated 
cost  of  labor  and  material  in  order  to  secure  the  bid  price  will  vary  with  differ- 
ent contractors,  but  the  percentage  mentioned  in  this  paragraph  is  about  what 
conservative  contractors  figure  on. 

It  must  be  distinctly  understood  that  the  data  given  in  the  foregoing 
tabulations  is  merely  an  estimate,  and  not  actual  cost  data.  This  estimate, 
however,  is  in  accordance  with  conservative  practice,  but  naturally  each  man  will 
have  his  own  ideas  concerning  prices.  The  estimate  shown  above  is  based  upon 
normal  conditions  of  20  working  days  per  month,and  fairly  reliable  railroad  ser- 
vice. An  unusually  good  or  bad  season  would  probably  change  these  figures  con- 
siderably. 


t 


Ill 


CHAPTER  XIII. 

THE  ADVANTAGES  AND  ECONOMIES  OF  LIGHT  RAILWAY  HAULAGE 


To  charge  a 4 hag  hatch  of  material  for  a 1-2-3  mixture  into  a paving 
mixer  by  means  of  wheelbarrows  and  shovels,  requires  the  following  minimum  organ- 
ization! 


3 - men  handling  cement 

1 - man  handling  empty  hags 

4 - men  wheeling  stone 

3 - men  wheeling  sand 

4 - men  shoveling  stone 

2 - men  shoveling  sand 

17  - men 

The  direct  charging  of  the  mixer  from  railway  cars, by  means  of  a small 
derrick  attached  to  the  mixer, requires  only  3 men,  thus  effecting  a saving  of  14 
men  over  the  method  of  charging  hy  hand.  At  $4*00  per  day  this  saving  amounts  to 
$56.00,  or  to  $1,232.00  per  20  day  month, allowing  pay  for  2 rainy  days.  Inasmuch 
as  the  average  rate  of  operation  for  a 14-E  paving  mixer  has  been  taken  at  1.25 
miles  of  road  per  month,  the  saving  in  labor  in  charging  the  mixer  effected  hy 
the  railway  method  over  the  hand  method  amounts  to  about  $1,000.00  per  mile.  If 
the  monthly  output  of  the  mixer  is  less  than  1.25  miles,  the  saving  in  labor  per 
mile  in  charging  will  he  even  greater.  It  is  difficult  to  get  men  to  perform  the 
heavy  labor  of  charging  a paving  mixer  by  means  of  wheelbarrows  and  shovels.  The 
elimination  of  this  heavy  labor,  due  to  direct  charging  of  the  mixer,  has  been 
known  to  decrease  the  labor  turnover  quite  materially.  Aside  from  the  actual 
financial  saving,  a reduction  of  14  men  in  the  size  of  the  gang  required  is  always 
worth  while  due  to  the  greater  independence  from  the  labor  market  resulting  there- 
from. 


BATCH  BOX  CHARGING  SYSTEM 


112 


If  the  mixer  is  charged,  direct  from  motor  trucks  equipped  with  a special  ! 
dump  body,  or  a regular  dump  body  subdivided  into  compartments,  2 men  will  be  re- 
quired at  the  charging  end  of  the  mixer,  providing  the  batches  in  the  motor  truck 
contain  cement.  In  some  states  specifications  prohibit  the  dumping  of  cement  in 
with  the  sand  and  stone,  and  require  a special  weather  tight  compartment  for  the 
cement.  Inasmuch  as  the  special  dump  bodies  with  which  motor  trucks  are  equipped 
are  generally  not  divided  into  separate  cement  compartments,  it  becomes  necessary 
to  haul  out  cement  in  bags  and  empty  it  into  the  mixer  by  hand.  In  such  a case 

I it  is  necessary  to  provide  at  least  2 more  men,  making  a total  of  4 in  the  charging 
crew  when  the  mixer  is  charged  direct  from  motor  trucks. 

One  of  the  most  difficult  and  expensive  operations  in  road  building  is 
trimming  the  subgrade  by  hand,  and  seldom  is  the  cost  less  than  $0.10  to  $0.15 
per  square  yard.  The  inexperienced  contractor  under-estimates  the  cost  of  trim- 
ming subgrade  by  hand  more  frequently  than  any  other  item,  and  there  is  hardly  a 
contractor  who  does  not  suffer  loss  in  this  operation.  The  price  for  grading  is 
generally  adequate  only  for  moving  the  earth,  and  all  too  frequently  the  profits 
from  earth  moving  are  absorbed  in  the  cost  of  fine  grading.  The  contractor  who 
has  had  experience  only  in  rough  grading,  seldom  appreciates  the  cost  of  the  fine 
grading  involved  in  preparing  a subgrade  for  a highway.  The  Laksv/ood  Engineering  \ 
Company,  of  Cleveland,  Ohio,  now  manufacture  a machine  for  trimming  subgrades. 

This  machine  is  adjustable  with  respect  to  the  depth  of  cut,  and  inasmuch  as  it 
operates  on  the  side  forms, it  is  possible  to  secure  a subgrade  almost  as  accurate 
as  the  surface  of  the  finished  pavement.  The  road  roller, or  a light  tractor,  is 
generally  used  to  pull  the  subgrader.  The  cost  of  trimming  the  subgrade  by  ma- 
chine is  about  $0.04  per  square  yard,  thus  effecting  an  econorry  over  hand  trim- 
ming of  about  $0.06  per  square  yard,  or  $635.00  per  mile  of  18  foot  road.  Machine 
trimming  of  the  subgrade  is  feasible  only  on  an  unobstructed  subgrade,  such  as 
that  which  characterizes  light  railway  haulage. 


UNOBSTRUCTED  SUB  GRADE  PERMITS  MACHINE  TRIMMING 

When  hauling  is  performed  over  the  subgrade  by  means  of  team  or  truck 
it  is  generally  necessary  to  retrira  a considerable  proportion  of  it,  and  after 
a rain  it  is  generally  necessary  to  retrim  all  of  the  subgrade.  If  only  one- 
fourth  of  the  area  must  be  retrimraed,  the  cost,  at  $0.10  per  square  yard,  would 


113 


amount  to  $265.00  per  mile  of  18  foot  road.  Light  railway  haulage  avoids  the 
necessity  for  retrimming  subgrade  because  no  hauling  is  done  over  it,  and  the 
subgrade,  once  finished,  need  not  be  touched  again. 


RE  TRIMMING  SUB  GRADE  DUE  TO  TRUCK  HAULAGE 

Motor  triicks  are  quite  commonly  used  in  certain  parts  of  the  country, 
to  charge  the  mixer  direct, as  illustrated  on  page  8 and  page  93.  While  this  method 
avoids  placing  material  on  the  subgrade  it  cuts  up  the  subgrade  quite  badly,  and 
wet  subgrade  results  in  serious  delay.  Where  weather  and  subgrade  conditions  are 
ideal  this  method  works  very  well,  but  it  does  not  possess  the  reliability  or 
economy  of  operation  of  light  railway  haulage, or  combined  light  railway  and  motor 
truck  haulage  where  the  trucks  operate  over  the  finished  pavement. 


RUTTED  SUBGRADE  DUE  TO  TRUCK  HAULAGE 


114 


Not  only  is  hand  trimning  troublesome  and  expensive,  but  it  is  inaccurate 
Seldom  is  a subgrade  trimmed  by  hand  accurate  to  within  l/4  inch  of  the  correct 
contour  and  elevation,  particularly  if  the  subgrade  is  crowned.  Under  the  rigid 
inspection  characteristic  of  road  building  today  hand  trimmed  subgrade  is  generally 
low,  and  the  experienced  contractor  always  makes  allowance  for  this.  Loss  due  to 
low  subgrade  is  considerably  greater  than  casual  consideration  would  indicate,  for 
a subgrade  l/4  inch  too  low  requires  75  cubic  yards  of  extra  concrete  per  mile  of 
18  foot  road  for  which  no  pay  is  received.  At  $18.00  per  cubic  yard,  the  loss 
would  amount  to  $1,320.00  per  mile.  If  only  half  the  subgrade  is  l/4  inch  lov;  or 
the  entire  subgrade  averages  l/8  inch  low,  the  loss  due  to  extra  concrete  will 
still  amount  to  the  very  considerable  figure  of  $660.00  per  mile. 


TRIMMING  SUB  GRADE  BY  HAND 


The  State  of  Pennsylvania  has  cut  a large  number  of  4 inch  diameter 
cores  from  roads  all  over  the  state,  and  the  majority  of  these  cores  indicate  that 
the  contractor  has  placed  at  least  l/z  inch  more  concrete  than  he  was  paid  for. 

In  certain  localities  loss  due  to  low  subgrade  might  be  balanced  by  the  saving 
effected  in  hi^i  spots,  but  a contractor  contemplating  work  in  states  with  well 
organized  highway  departments  will  show  wisdom  by  not  expecting  to  compensate  his 
loss  from  low  subgrade  by  leaving  high  spots.  The  tendency  in  highway  engineering 
is  to  pay  much  stricter  attention  to  the  subgrade  than  heretofore,  and  there  is 
but  little  chance  of  a contractor’sbeing  permitted  to  leave  a subgrade  high.  Loss 
due  to  low  subgrade  is  one  of  the  most  common  in  highway  construction,  and  is  one 
of  the  most  difficult  to  overcome.  Machine  trimming  of  the  subgrade  will  insure 
accuracy,  and  this  is  one  of  the  big  advantages  of  light  railway  haulage.  The 
photograph  on  the  following  page  illustrates  a machine  trimmed  subgrade. 

When  material  is  dunped  on  the  subgrade, a very  considerable  loss  occurs 
due  to  the  mixing  of  dirt  with  it,  grinding  material  into  the  subgrade  by  the 
wheels  of  vehicles  employed  in  hauling  it,  the  effect  of  weather,  and  inaccurate 
placing.  When  material  is  dumped  on  the  subgrade  in  long  windrows  for  a mile  or 
so  it  remains  there  for  about  a month,  and  the  loss  which  is  liable  to  result  fe 
apparent.  The  accurate  placing  of  material  on  the  subgrade  is  very  difficult. 

In  case  insufficient  material  has  been  distributed  a long  -v^ieelbarrow  haul  is  in- 
volved, with  consequent  increased  cost  and  decreased  output,  until  more  material 


115 


can  be  hauled  in  over  the  piles  already  in  place.  This  is  a very  difficult 
proceeding,and  the  effect  on  the  material  already  in  place  needs  no  comment.  In 
order  to  provide  against  delay  due  to  insufficient  material  a surplus  is  frequent- 
ly provided,  though  this  surplus  very  often  occurs  unintentionally  due  to  in- 
accurate distribution.  When  a surplus  of  material  occurs  there  are  generally  no 
facilities  for  removing  it  without  seriously  delaying  the  concrete  mixer,  and  the 
cheapest  thing  to  do  is  to  throw  it  onto  the  shoulder.  Ifeterial  so  placed  on  the 
shoulder  is  wasted,  because  by  the  time  the  pavement  is  sufficiently  cured  to 
permit  traffic  it  has  become  dirty  and  the  cost  of  reclaiming  it  is  more  than  it 
is  worth.  When  we  consider  all  these  factors  and  the  fact  that  failure  to  scrape 
up  the  last  half  inch  at  the  bottom  of  a pile  dumped  from  a truck  or  a wagon  in- 
volves a loss  of  approximately  5 per  cent,  it  is  apparent  that  a loss  of  10  per 
cent  due  to  dumping  material  on  the  subgrade  is  quite  likely  to  occur.  Experiencec 
contractors,  when  employing  the  method  of  dumping  material  on  the  subgrade,  make 
an  allowance  for  loss  of  approximately  10  per  cent.  A loss  of  10  per  cent  of  sand 
and  stone  would  amount  to  about  $1,000.00  per  mile  of  18  foot  road,  if  the  cost 
of  the  material  on  the  road  is  only  $3.50  per  cubic  yard.  Direct  charging  of  the 
mixer  by  light  railway  or  motor  truck  haulage,  will  eliminate  this  loss. 


y 


MACHINE  TRIMMED  SUB  GRADS 

The  central  unloading  and  proportioning  yard  characteristic  of  railway 
haulage,  is  very  well  adapted  to  the  use  of  bulk  cement.  Bulk  cement  is  quoted 
at  $0.05  per  barrel  less  than  bagged  cement  by  practically  all  cement  companies, 
and  the  final  saving  due  to  elimination  of  lost  bags,  etc.  should  amount  to  some 
$0.15  per  barrel  over  bagged  cement.  On  a mile  of  18  foot  concrete  road,  the 
saving  due  to  bulk  cement  at  $0.15  per  barrel  will  amount  to  about  $560.00.  Bulk 
cement  might  be  used  when  mixers  are  charged  direct  by  motor  trucks,  but  motor 
trucks  seldom  possess  separate  water  tight  compartments  for  the  cement  and  many 
states  will  not  permit  the  cement  to  be  mixed  with  the  sand  or  stone  enroute  to 
the  mixer.  In  case  bagged  cement  is  used,  the  central  unloading  and  proportion- 
ing plant  will  effect  a considerable  economy  due  to  reduction  in  lost  and  wet 
bags.  A loss  of  5 per  cent  can  easily  occur  when  bags  are  hauled  out  on  the  road, 
and  at  $0.25  per  bag  this  loss  amounts  to  about  $190.00  per  mile  of  road.  With 
a central  unloading  and  proportioning  yard,  the  bags  need  never  leave  the  cement 
shed. 


* 


116 


LOST  MATERIAL  RESULTING  FROM  DUMPING  ON  GROUND 


Inability  to  operate  over  wet  subgrade  is  one  of  the  most  serious 
handicaps  to  road  building,  when  a system  is  used  which  involves  hauling  over  the 
subgrade.  Just  what  delay  due  to  wet  weather  means  in  dollars  and  cents  to  a 
contractor  is  difficult  to  say,  but  it  can  easily  mean  the  entire  difference  be- 
tween profit  and  loss  or  between  finishing  a job  the  current  season  or  carrying  it 
over  the  winter  to  the  next  year.  This  latter  possibility  is  a very  serious  one, 
and  a contractor  should  do  everything  possible  to  avoid  it.  During  a normal  season 
bad  weather  is  generally  the  greatest  risk  with  which  a contractor  must  contend, 
and  anything  which  will  minimize  this  risk  is  of  paramount  importance.  Complete 
light  railway  haulage,  or  the  combined  light  railway  and  motor  truck  system,  will 
reduce  delay  from  rain  to  a minimum,  as  well  as  permit  work  to  be  started  earlier 
in  the  spring, than  if  a method  of  operation  is  used  which  involves  hauling  over 
earth  roads.  There  are  no  general  figures  available  showing  the  increased  seasonal 
output  resulting  from  the  use  of  light  railway  haulage,  but  it  is  understood  that 
in  Pennsylvania  contractors  so  equipped  have  produced  an  appreciably  greater  mile- 
age of  road  than  those  wh o hauled  over  earth  road. 

When  a system  of  haulage  is  used  which  does  not  permit  material  to  be 
hauled  past  the  uncured  concrete,  it  is  necessary  to  delay  starting  the  concrete 
mixer  until  all,  or  a considerable  proportion,  of  the  grading  between  the  material 
yard  and  the  far  end  of  the  road  is  complete.  Sometimes  it  is  possible  to  haul 
thru  the  grading  operations, or  around  them  on  a side  road.  The  difficulty  of 
hauling  thru  grading  operations  in  case  of  wet  weather,  or  in  case  of  heavy  cuts 
and  fills,  needs  no  further  comment.  Good  side  roads  are  very  difficult  to  find, 
and,  when  they  do  exist,  the  length  of  haul  is  generally  considerably  increased 
thereby.  If  the  road  is  constructed  in  an  entirely  new  location,  it  is  generally 
necessary  to  delay  concreting  until  all  of  the  grading  has  been  finished.  In  most 
cases  when  team  or  truck  haulage  is  used, the  concrete  mixer  cannot  be  started 
until  all  of  the  grading  between  the  material  yard  and  the  far  end  of  the  road  has 
been  finished.  When  concreting  is  finally  started,  it  is  necessary  to  start  at 
the  point  of  maximum  haul, when  material  is  hauled  by  team  or  truck.  Not  only  is 
considerable  del^y  incurred,  but  the  only  payments  received  from  the  state  for  the 
first  few  months  are  for  grading.  When  concreting  is  finally  started  minimum  pay- 
ments for  this  class  of  work  will  result,  due  to  the  fact  that  the  most  expensive 
portion,  the  long  haul  portion,  is  done  first.  The  inexperienced  organization  is 


' / 


» 


117 


called  upon  to  do  the  most  difficult  part  of  the  work  first,  and  is  further  handi- 
capped by  the  many  chances  for  delay  involved  in  the  long  haul  over  the  earth 
subgrade* 

When  light  railway  haulage  is  used,  either  by  itself  or  in  conjunction 
with  motor  trucks,  it  is  possible  to  start  the  mixer  at  the  point  of  minimum  haul, 
because  hauling  can  be  carried  on,past  the  uncured  concrete,on  the  shoulder  of  the 
road.  The  concrete  mixer  can  thus  be  started  as  soon  as  a few  hundred  feet  of 
subgrade  have  been  prepared,  eliminating  the  delay  which  is  generally  necessary 
when  a type  of  haulage  is  used  which  cannot  operate  past  the  uncured  concrete. 

The  placing  of  concrete  and  grading  is  carried  on  simultaneously,  and  the  most 
profitable  portion  of  the  concrete,  the  short  haul  portion,  is  done  first.  All 
this  insures  a large  payment  from  the  state  early  in  the  life  of  the  job,  thus 
providing  working  capital  which  is  generally  so  urgently  needed  at  this  time. 

This  plan  of  operation  also  insures  that  all  of  the  track  is  well  bedded  and  the 
organisation  experienced,  by  the  time  the  long  haul  portion  of  the  wrk  is  reached* 
The  most  critical  time  in  the  life  of  a job  is  at  the  beginning,  for  then  every- 
thing is  literally  going  out  and  nothing  coming  in.  The  most  difficiilt  problem 
with  which  the  majority  of  contractors  have  to  contend,  is  to  finance  the  operation 
until  payments  from  the  state  are  sufficient  to  carry  the  job.  Lack  of  working 
capital  at  the  beginning  of  a job  is  a common  source  of  embarrassment  to  many 
contractors,  and  many  failures  result,  not  from  low  bid  prices,  but  from  lack  of 
money  during  the  first  few  months.  In  the  opinion  of  many  contractors, the  biggest 
advantage  of  li§dit  railway  haulage  is  the  fact  that  it  enables  the  concrete  mixer 
to  start  at  the  point  of  minimum  haul  with  but  little  delay,  and  permits  simul- 
taneous performance  of  concreting  and  grading. 


The  light  railway  haulage  system,  whether  used  by  itself  or  in  con- 
junction with  motor  trucks,  requires  fewer  men  than  any  other  system.  Not  only 
are  fewer  men  required,  but  the  operation  of  this  system  appeals  to  the  mechanical 
instinct  in  most  men  with  the  result  that  they  become  interested  and  attached  to 
their  work.  Heavy  labor  is  eliminated,  and  a premium  placed  upon  intelligence  and 
skill.  In  many  instances, the  adoption  of  light  railway  haulage  has  resulted  in 
a decreased  labor  turnover. 


LIGHT  RAILYAY  HAULAGE  ELIMINATES  HEAVY  LABOR 


I 


118 


CHAPTER  XIV. 


TffS  MINIMUM  SIZE  OP  JOB  JUSTIFYING  A LIGHT  BAILWAY  PLANT 


A complete  light  railway  road  building  plant  is  a comparatively  expen- 
sive proposition,  and  while  there  is  practically  no  limit  to  the  maximum  size  of 
job  to  which  it  can  be  applied  there  is  a limit  to  the  minimum  size  of  job  on 
which  it  is  economically  justified.  This  limitation  applies  to  equipment  of  all 
kinds,  but  especially  to  light  railway  equipment  which,  unlike  teams  or  motor 
trucks,  cannot  generally  be  rented  and  must  be  purchased.  When  light  railway 
equipment  is  rented,  the  rental  charge  is  so  high  that  it  is  cheaper  to  purchase 
it.  While  a li^it  railway  plant  will  effect  the  same  economies  on  a small  job  as 
on  a larger  one,  the  plant  charges  on  a small  job  might  be  such  as  to  absorb  all 
of  the  economies  effected,  thus  leaving  no  economic  justification  for  the  invest- 
ment. The  purpose  of  this  chapter  is  to  determine,  in  a general  way,  the  minimum 
size  of  job  which  will  justify  investment  in  a complete  light  railw/ay  road  building 
plant . 

Investment  in  a light  railway  road  building  plant,  or  in  any  other  plant, 
is  economically  justified  when  the  net  savings  effected  by  that  plant  over  other 
methods  is  such  as  to  give  a satisfactory  return  on  the  additional  investment,  if 
any,  necessary  to  secure  such  a plant.  The  solution  of  this  problem  thus  hinges 
largely  upon  the  question  of  what  is  considered  a satisfactory  return  on  the  in- 
vestment, and  naturally  this  will  vary  with  circumstances  and  individual  judgment. 
What  one  man,  under  certain  conditions,  considers  a satisfactory  return,  might  be 
considered  entirely  inadequate  by  another.  Some  men  might  invest  in  a complete 
railway  plant  for  a certain  job,  even  though  this  plant  will  not  yield  a greater 
net  return  on  this  particular  job  than  a cheaper  plant,  because  they  intend  later 
on  to  apply  it  to  another  job  which  will  justify  the  investment.  It  is  thus 
apparent  that  a large  number  of  opinions  prevail  as  to  the  minimum  size  of  job 
which  will  justify  a plant.  In  this  thesis,  however,  we  will  assume  that  a light 
railway  plant  is  justified, when  the  net  saving  effected  amounts  to  20  per  cent  of 
the  increased  cost  over  some  other  type.  If  a net  return  of  less  than  20  per  cent 
is  considered  satisfactory,  the  investment  can  be  justified  on  a smaller  job. 

Another  factor  which  affects  this  problem  very  materially,  is  the  propor- 
tion of  yearly  plant  charges  assigned  to  each  job.  If  a contractor  has  only  one 
job,  this  job,  no  matter  how  small,  must  carry  all  of  the  yearly  plant  charges. 

If  a number  of  small  jobs  are  available,  however,  so  located  that  one  plant  can  be 
applied  to  each  in  turn,  it  is  possible  to  justify  the  investment  on  a smaller  job 
than  if  only  one  is  available.  It  is  principally  when  considering  the  initial 
investment,  that  the  question  of  the  minimum  size  of  job  which  will  economically 
justify  a certain  plant  is  of  importance.  After  the  plant  has  been  purchased  it 
will  undoubtedly  be  applied  to  jobs  of  all  sizes,  because  plant  charges  are  almost 
as  great  on  an  idle  plant  as  on  a busy  one. 

The  economies  which  the  light  railway  system  of  road  building  wrill 
effect  over  the  old  system  of  dumping  material  on  the  subgrade  and  charging  the 
mixer  by  hand,  has  been  discussed  in  detail  in  the  proceeding  chapter.  For  con- 
venience, these  economies  will  be  summarized  below: 


119 


Saving  in  labor  in  charging  mixer .............. . $1,000.00 

Saving  in  labor  in  trimming  subgrade 635.00 

Saving  in  labor  in  retriraming  subgrade 265.00 

Elimination  of  lost  material 1,000*00 

Elimination  of  extra  concrete 660.00 

Saving  due  to  use  of  bulk  cement 560*00 

Saving  per  mile  $4,120*00 


On  the  average  small  team  or  truck  job,  a portable  bin  equipped  with  a 
bucket  elevator  or  an  elevating  skip  is  used  for  unloading  material  from  railroad 
cars  and  loading  into  trucks  or  wagons.  A bin  of  this  type  is  illustrated  on 
page  82.  Such  a bin,  of  50  ton  capacity,  costs  about  $1,800*00.  A crane  equipped 
with  a 3/4  yard  clam  shell  bucket,  such  as  is  commonly  used  in  unloading  material 
for  a light  railway  plant,  costs  about  $10,000.00.  On  the  average  small  job, 
material  is  stored  on  the  subgrade  in  windrows,  and  in  order  to  store  the  same 
quantity  insured  by  a tunnel  150  feet  long  it  is  necessary  to  place  material  on  the 
subgrade  for  a distance  of  1 mile.  Very  seldom  is  material  stored  on  the  subgrade 

for  more  than  a mile  ahead  of  the  mixer,  so  in  making  our  comparison  we  will  assume 

a tunnel  150  feet  long.  Such  a tunnel,  equipped  with  traps  every  8 feet,  will  cost 
about  $2,000.00.  The  cost  of  the  unloading  equipment  required  by  a light  railway 
plant,  will,  therefore,  exceed  that  commonly  used  on  a small  team  or  truck  job  by 
some  $10,200*00.  Considering  everything,  the  unit  cost  of  unloading  will  not 
differ  greatly  with  either  method* 

In  computing  the  cost  of  haulage,  it  will  be  assumed  that  teams  are  hired 

for  $10*00  a day  and  5 -ton  motor  trucks  for  $40.00  a day.  The  railway  equipment 

will  be  proportioned  for  three-fourths  of  the  maximum  haul,  and  all  the  plant 
charges  for  the  year  will  be  assigned  to  the  particular  job  in  mind.  The  rate  of 
operation  of  a 14-E  paving  mixer,  will  be  taken  at  1*25  miles  of  18  foot  concrete 
road  per  20  working  day  month.  The  type  of  road  will  be  assumed  to  be  concrete, 

18  feet  wide,  with  an  average  thickness  of  7-1/3  inches  and  proportions  of  1-2-3. 
The  length  will  be  taken  at  5 miles. 

At  a rate  of  1*25  miles  per  month,  approximately  4 months  will  be  re- 
quired to  place  the  concrete  on  this  road.  Due  to  the  greater  possibility  of  de- 
lay from  rain  when  material  is  hauled  over  the  subgrade  by  teams  or  motor  trucks, 
it  would  seem  to  be  reasonable  to  assume  the  output  of  the  mixer  at  1 mile  per 
month.  In  making  our  comparison,  however,  the  greater  possibility  of  delay  from 
rain  when  team  or  truck  haulage  is  used  will  be  ignored,  but  an  allowance  of  pay 
for  10  per  cent  of  the  time  due  to  rainy  weather  will  be  made. 

The  quantity  of  material  needed  in  a road  of  this  type  and  length,  based 
upon  weights  of  376  pounds  per  barrel  of  cement,  3,000  pounds  per  cubic  yard  of 
sand,  and  2,700  pounds  per  cubic  yard  of  stone,  is  as  follows: 

18,850  bbls*  cement  or  3,544  tons 
5,600  cu.yds.  sand  or  8,400  tons 
8,400  cu.yds*  stone  or  11.540  tons 

23,284  tons 

On  the  average  haul  of  2-1/2  miles,  a team  will  make  a round  trip  under 
good  conditions  in  130  minutes  or  4-l/2  trips  per  10  hour  day.  This  is  at  a speed 
of  2-l/2  miles  per  hour,  allowing  5 minutes  for  dumping  and  5 minutes  for  loading. 
To  deliver  the  total  of  11,600  team  loads  of  2 tons  each,  will  thus  require  580 
team  days. 


• - i. 


* 


. 

. 


. 

■ 


120. 


A 5 ton  motor  truck  should  operate  at  a speed  of  6 miles  per  hour  loaded 
and  10  miles  per  hour  empty  over  earth  subgrade,  with  an  allowance  of  5 minutes 
for  loading  sand  or  stone  and  10  minutes  for  dumping  and  getting  away.  An  allow^- 
ance  of  20  minutes  for  loading  a 26  "barrel  load  of  cement  and  the  same  amount  of 
time  for  unloading,  should  be  made.  On  the  average  haul  of  2-l/2  miles,  therefore, 
a truck  should  make  11  round  trips  per  day  hauling  sand  or  stone,  and  7 round  trips 
hauling  cement.  A total  of  465  truck  days  are  thus  required  to  haul  the  4,660 
loads  of  5 tons  each. 

Based  upon  a haul  of  3.75  miles  and  a speed  of  6 miles  per  hour,  allow- 
ing 5 minutes  for  switching  trains  at  the  mixer  and  5 minutes  at  the  material  yard, 
a locomotive  should  make  a round  trip  in  85  minutes.  This  is  at  the  rate  of  7 
round  trips  per  10  hour  day,  so  that  1 locomotive  hauling  a 7 -car,  14 -"batch, train 
should  deliver  98  "batches  to  the  mixer.  Three  6 -ton  locomotives  and  5 - 7 -car 
trains  are  thus  required.  The  amount  and  cost  of  the  railway  equipment  is  shown 
below. 


BURTON  6 TON  LOCOMOTIVE  HAULING  8 CAR  TRAIN 


EQUIPMENT 

COST 

25 

miles  track 

@ 

$ 6,318*40 

$ 33,171.60 

12 

half  turnouts 

@ 

150.00 

1,800.00 

24 

curved  sections 

@ 

13.95 

334.80 

3 

6- ton  locomotives 

@ 

4,600.00 

13,800.00 

70 

batch  boxes, 25  cu.ft. 

cap* 

71.20 

4,984.00 

35 

batch  box  cars 

@ 

115.00 

4.025.00 
$ 58,115.40 

The  cost  of  operation  of  the  three  systems  considered,  should  be  about 
as  follows  on  this  particular  job,  allowing  pay  for  10  per  cent  lost  time  due  to 
rain  to  the  hired  teams  and  trucks: 


121 


RAILWAY 


TEAM 


TRUCK 


3 loco,  operators,  4 months 

® $120.00 

$1,440 

3 train  men,  80  days 

@ 

4.00 

960 

Gas  & oil,  per  loco.  90  days 

® 

5.00 

1,350 

Lay  & remove  7 mi.  track 

@ 

200.00 

1,400 

Plant  charge  on  track 

@ 

3°!$ 

10,768 

Plant  charge  on  locos 

@ 

52  j 

7,176 

Plant  charge,  cars  and  boxes 

@ 

::i  34  % 

3,063 

Load  & unload  381  tons  equip. 

@ 

2.00 

762 

Freight,  per  cwt. 

@ 

0.44 

3,353 

Rental  of  teams. 

@ 

10.00 

Rental  of  trucks 

@ 

40.00 

$30,267 

$28,380 


$28,380 


$20.460 

$20,460 


The  cost  of  operation  by  the  railway  method,on  this  particular  job,  is 
estimated  to  exceed  the  cost  by  teams  by  $1,887. 00, and  the  cost  by  trucks  by 
$9,807.00.  The  initial  investment  in  the  railway  hauling  and  unloading  plant 
exceeds  that  in  the  team  or  truck  plant,  which  is  merely  hired  by  the  day,  by 
,315.00.  The  saving  effected  by  the  railway  plant  has  previously  been  shown  to 
be  some  $4,120.00  per  mile,  over  the  team  or  truck  system  where  material  is  dumped 
on  the  subgrade  and  charged  into  the  mixer  by  hand.  The  total  saving  on  this  job 
would,  therefore,  amount  to  approximately  $20,600.00.  Subtracting  the  increased 
cost  of  operation  by  the  railway  method  leaves  a net  saving  of  $19,738.00  over  the 
team  method,  and  $11,818.00  over  the  truck  method.  These  savings  amount  to  29  per 
cent  and  19  per  cent, respectively,of  the  additional  initial  investment  of  $68,315. 
in  the  railway  plant  over  the  other  methods  of  doing  the  work. 

We  have  previously  assumed  that  a net  return  of  20  per  cent  on  the 
additional  investment  is  sufficient  to  justify  a complete  railway  plant.  Inasmuch 
as  this  assumption  was  arbitrary,  it  seems  safe  to  say  that,  with  the  unloading 
point  at  one  end  and  material  dumped  on  the  subgrade,  a complete  railway  plant  can 
be  economically  justified  on  a 4-l/2  mile  job,  when  compared  with  team  haulage, 
and  on  a 5 mile  job  when  compared  with  truck  haulage.  This  comparison  is  made 
with  teams  and  trucks  hired  by  the  day.  If  the  contractor  owned  the  teams  or 
trucks  he  would  be  compelled  to  consider  plant  charges  on  them,and  the  railway 
plant  could  be  justified  on  a smaller  job  than  those  indicated  above, inasmuch  as 
the  difference  in  the  initial  investment  in  these  several  plants  would  be  greatly 
reduced. 

By  proceding  in  the  manner  outlined  in  the  foregoing,  a complete  railway 
plant  can  be  shown  to  be  economically  justified  over  a hired  team  or  motor  truck 
plant. on  a 3-l/2  or  4 mile  job*  when  the  unloading  point  is  near  the  middle  of  the 
job  and  immediately  adjacent  to  it,  or  up  to  2 miles  away.  In  the  same  manner  it 
is  possible  to  show  that  a combined  ligfrt  railway  and  motor  truck  plant,  in  which 
the  trucks  are  hired  at  the  rate  of  $40.00  per  day,  can  be  justified  on  a job 
2-l/2  to  3 miles  in  length,when  compared  with  a hired  team  or  truck  plant  dumping 
material  on  the  subgrade. 

All  of  the  foregoing  is  based  upon  the  assumption  that  the  entire  yearly 
plant  charges  must  be  absorbed  by  only  one  job.  If  more  than  one  job  is  available, 
so  that  a portion  of  the  plant  charges  can  be  assigned  to  each,  it  is  apparent 
that  investment  in  a complete  railway  plant  can  be  justified  on  a considerably 
smaller  job  than  if  one  job  alone  must  carry  the  entire  plant  charge.  If  a rate 
of  return  of  less  than  20  per  cent  on  the  additional  initial  investment  required 


122 


for  the  railway  plant  is  considered  satisfactory,  investment  in  a railway  plant 
can  be  justified  on  smaller  jobs  than  those  indicated  above. 

Other  factors  besides  the  strictly  financial  one  must  sometimes  be  con- 
sidered, when  deciding  whether  or  not  a certain  job  will  justify  investment  in  a 
railway  plant.  The  difficulty  of  securing  labor  or  of  starting  work  early  in  the 
spring,  might  be  such  as  to  induce  a contractor  to  use  a railway  plant  when  per- 
haps it  might  be  more  economical,  under  normal  conditions,  to  use  some  other  method 

In  making  the  comparison  between  the  railway  plant  and  the  team  or  truck 
plants,  we  have  practically  placed  them  all  on  the  same  basis  as  far  as  reliability 
of  operation  is  concerned.  If  weather  and  soil  conditions  are  good  this  assumption 
might  be  correct,  but  during  a wet  season  and  in  certain  soils  there  is  no  doubt 
but  that  the  railway  system  would  possess  big  advantages  over  the  other  systems. 
Furthermore,  the  team  and  truck  equipment  was  based  upon  the  average  haul,  while 
the  railway  equipment  was  based  upon  three-fourths  of  the  maximum  haul.  At  points 
beyond  the  average  haul,  therefore,  the  team  or  truck  equipment  provided  would  not 
have  sufficient  capacity  to  keep  the  mixer  going  at  its  maximum  rate.  All  these 
factors  must  be  kept  in  mind  in  deciding  upon  the  minimum  size  of  job  which  will 
justify  investment  in  a complete  railway  plant,  and  the  financial  factor,  while 
admittedly  of  great  importance,  is  not  the  only  one  to  be  considered.  Each  job 
possesses  its  own  peculiar  factors,  and  must  be  studied  by  itself.  In  the  absence 
of  specific  knowledge  concerning  local  conditions,  and  for  general  use,  the  deter- 
mination made  in  the  preceeding  paragraphs  can  be  used  as  a guide.  As  previously 
stated  a determination  of  this  kind  is  of  importance  principally  when  considering 
the  initial  investment,  for  after  the  equipment  has  been  purchased  it  will  un- 
doubtedly be  used  on  jobs  of  all  sizes. 

A comparison  of  a light  railway, or  a combined  light  railway  and  motor 
truck  system/with  any  other  method,  can  be  n&de  in  the  manner  outlined  in  this 
chapter . 


123. 


CHAPTER  XV. 


present  tendencies  in  highway  construction. 


Until  a few  years  ago  highway  construction  has  been  considered  a small 
man’s  game,  in  fact  the  building  of  hi^diways  was  more  or  less  sporadic  with  no 
serious  attempt  at  quantity  production.  The  equipment  used  had  been  developed 
more  or  less  by  rule  of  thumb,  and  was  not  really  capable  of  producing  roads  in 
large  quantity.  No  real  attempt  had  been  made  to  produce  high  class, labor  saving 
equipment,  and  the  type  of  equipment  used  and  the  methods  employed  varied  with 
practically  every  contractor.  The  organization  for  building  highways  was  not 
well  developed  or  efficient,  and  the  quantity  and  quality  of  the  roads  was  of 
corresponding  character.  Contracts  were  awarded  for  such  small  sections  as  to 
preclude  the  use  of  any  considerable  amount  of  labor  saving  equipment,  or  to 
attract  the  attention  of  large  contracting  organizations. 

About  two  years  ago  a radical  change  was  effected  in  the  highway  con- 
struction field,  in  answer  to  the  great  demand  for  good  roads  which  the  war 
developed,  or  at  least  accelerated.  A number  of  equipment  manufacturers  for  some 
years  previously  had  been  working  on  a theory  that  methods  of  highway  construction 
then  in  use  were  bound  to  be  superseded  by  more  efficient  methods,  and  had  de- 
signed greatly  improved  machinery  . They  foresaw  that  in  order  to  build  the  mile- 
age of  good  roads  necessary  in  this  country,  the  production  of  good  roads  must  be 
greatly  increased.  In  order  to  effect  this  increase  it  was  necessary  to  award 
large  contracts,  and  to  introduce  methods  coranon  to  other  large  construction  pro- 
jects. Large  contracts  naturally  attracted  larger  organizations,  whose  experience 
and  financial  resources  were  such  as  to  warrant  the  building  of  high  class  road 
construction  equipment  intended  for  quantity  production. 

About  this  same  time  the  highway  engineering  profession  thruout  the 
country  realized,  as  the  result  of  heavy  motor  truck  traffic  incident  to  war  work, 
that  our  trunk  line  highways  must  be  made  considerably  heavier  and  better. 

Heavier  construction  naturally  involves  a greater  amount  of  labor,  and  labor  saviii 
equipment,  therefore,  was  in  demand.  The  shortage  of  labor  which  has  prevailed 
thruout  the  country  ever  since  the  war  began,  except  during  the  winter  of  1920-21, 
was  another  incentive  for  adopting  labor  saving  equipment. 

Not  only  must  our  roads  be  made  heavier  but  they  must  be  made  better, 
and  highway  engineers  are  today  devoting  more  time  and  study  to  the  details  of 
construction  than  ever  before.  In  order  to  increase  the  quality  of  our  roads  it 
was  necessary  to  eliminate  many  of  the  uncertainties  which,  up  to  the  present 
time,  have  characterized  highway  engineering.  The  research  work  of  Professor 
Duff  Abrams  at  Lewis  Institute,  Chicago,  during  the  past  six  years,  has  demon- 
strated that  a large  proportion  of  the  potential  strength  of  concrete  is  wasted 
by  the  use  of  an  excessive  amount  of  water.  For  some  years  highway  engineers 
had  realized  that  the  use  of  too  much  water  was  a detriment  to  the  quality  of  the 
road,  but  they  were  forced  to  compromise  on  account  of  the  limitations  imposed  by 
hand  construction  methods.  The  finishing  machine,  which  subjects  the  concrete 
to  a thoro  tamping  action,  enabled  highway  engineers  to  employ  dryer  mixtures  in 
accordance  with  the  discoveries  of  Professor  Abrams.  That  this  results  in  im- 
proved quality  has  been  demonstrated  by  tests  on  cores  from  both  hand  and  mchine 
finished  concrete  roads,  which  have  been  cut  out  and  tested  by  the  Pennsylvania 
and  Illinois  Highway  Departments. 


124 


For  years  highway  engineers  have  attempted  to  secure  a smooth,  uniformly 
compacted  subgrade,  but  with  hand  construction  methods  this  has  been  practically 
impossible  at  a reasonable  cost.  A machine  for  trimming  subgrade,  illustrated 
in  the  foregoing  pages,  is  now  on  the  market.  This  machine  is  no  doubt  but  the 
forerunner  of  much  more  elaborate  and  efficient  machines  in  the  future.  Not  only 
does  machine  trimming  of  the  subgrade  assure  the  highway  engineer  of  the  desired 
smoothness  in  the  subgrade,  but  it  eliminates  a lot  of  trouble  and  expense  to  the 
contractor.  Machine  trimming  of  the  subgrade  should  result  in  both  improved  qual- 
ity and  decreased  cost  of  our  highways. 

Highway  engineering  to  date  has  really  been  more  of  an  art  than  a science 
But  little  attempt  has  been  made  to  discover  the  reasons  for  certain  practices 
which  have  prevailed  for  years,  and  highway  construction  has  largely  been  covered 
by  precedent.  At  the  present  time  highway  engineers  are  realizing  that  a vast 
and  practically  untouched  field  of  research  is  open  to  them,  and  the  demand  of 
modern  heavy  traffic  and  anticipated  future  traffic  has  forced  them  to  acknowledge 
that  our  present  knowledge  of  highways  and  hi^iway  construction  is  inadequate,  to 
say  the  least.  The  leading  highway  departments  have  established  laboratories 
whose  function  is  not  merely  to  conduct  routine  tests  on  materials,  but  to  carry 
out  field  investigations  on  a large  scale.  In  order  to  obtain  knowledge  of  mater- 
ial as  it  exists  in  the  finished  pavement,  many  highway  departments  have  equipped 
themselves  with  core  drilling  outfits.  With  these  outfits  cores  are  cut  from 
existing  pavements  of  all  kinds,  and  special  attention  can  be  given  to  roads  or 
portions  of  roads  which  have  failed.  These  investigations  promise  to  yield 
valuable  results  during  the  next  decade. 

Not  only  can  experiments  be  carried  out  on  cores  cut  from  roads,  but 
much  valuable  data  can  be  gained  from  a study  of  subgrade  conditions.  Heretofore 
our  knowledge  of  subgrade  conditions  has  been  very  meager,  and  has  been  largely 
theoretical.  The  possibility  of  studying  the  subgrade  in  order  to  determine  the 
relative  amount  of  frost  and  moisture  under  the  center  of  the  road  and  at  the 
shoulders,  the  bearing  power  at  different  seasons  of  the  year,  etc.  is  being 
realized  by  many  highway  departments,  and  should  yield  valuable  results. 

The  great  '’unknown"  in  highway  engineering  today,  as  in  the  past,  is 
the  subgrade.  Heretofore  subgrade  has  been  taken  for  granted  as  found,  and  but 
very  little  attempt  has  been  made  to  modify  existing  conditions  so  as  to  secure 
a subgrade  of  the  proper  character.  True,  the  necessity  for  drainage  has  long 
been  realized,  but  the  provisions  for  drainage  were  largely  based  upon  precedent 
and  were  more  or  less  superficial  and  inadequate.  Highway  engineers  have  not 
looked  at  the  problem  of  drainage  from  the  same  point  of  view  as  the  drainage 
engineer,  and  tile  of  a certain  size  has  been  placed  in  a certain  position,  irre- 
spective of  the  character  of  the  soil,  just  because  that  particular  practice  had 
always  prevailed.  The  same  type  of  pavement  and  the  same  type  of  drainage  were 
used  in  all  localities,  and  in  all  soils.  The  attitude  of  highway  officials,  who 
were  not  engineers,  and  of  the  public,  which  demanded  the  greatest  mileage  of 
improved  road  for  its  money,  was  no  doubt  largely  responsible  for  the  neglect  of 
proper  attention  to  subgrade  conditions.  Money  placed  in  a drainage  system  is  not 
apparent  on  the  surface  and  is  not  as  effective  for  political  purposes,  as  an  in- 
creased mileage  of  pavement.  In  spite  of  all  this,  however,  the  highway  engineer 
is  somewhat  to  blame  for  not  insisting  more  firmly  on  proper  preparation  of  the 
foundation.  At  the  present  time  the  sentiment  is  rapidly  growing  among  the  high- 
way profession  that  the  most  important  factor  in  the  success  of  a road  is  a proper 
foundation,  in  fact  it  is  hardly  too  much  to  say  that  a good  road  consists  pri- 
marily of  a properly  designed  drainage  system  surfaced  with  some  type  of  material 
which  will  resist  distortion  and  abrasion  fairly  well.  Drainage  systems  will  no 


125* 


doubt  become  more  elaborate  as  time  goes  on,  and  the  system  employed  today  will 
probably  seem  rather  puny  and  inadequate  by  comparison. 

The  United  States  Office  of  Public  Roads,  the  Federal  Highway  Council, 
which  is  affiliated  with  the  National  Research  Council,  and  all  the  leading  State 
Highway  Departments  are  now  carrying  on  extensive  investigations  of  soil  physics 
and  methods  of  properly  preparing  and  maintaining  the  foundation  for  a road.  All 
of  these  efforts  should  produce  valuable  information  during  the  next  decade,  and 
our  present  conception  of  proper  highway  construction  will  no  doubt  be  changed  con- 
siderably. The  tendency  of  the  day  is  toward  intensive  study  and  research,  in 
order  to  make  of  highway  engineering  more  of  a science  and  less  of  an  art  than  it 
has  been  heretofore. 

Up  to  the  present  time  most  of  the  research  work  on  highway  construction 
methods  and  material  has  been  carried  on  by  commercial  organizations  who  were  fi- 
nancially interested  in  the  subject,  and  highway  engineers  have  been  prone  to 
accept  the  results  of  these  investigations  without  taking  it  upon  themselves  the 
responsibility  for  research  work.  Happily  highway  engineers  are  now  realizing 
that  the  responsibility  of  carrying  on  research  work  for  improving  types  of  road 
and  methods  of  construction  is  theirs,  and  they  are  beginning  to  assume  their 
rightful  leadership  in  this  field. 

Until  quite  recently  highway  engineers  have  concerned  themselves  almost 
entirely  with  the  technical  details  of  road  building,  and  have  paid  but  little 
attention  to  construction  methods.  Engineers  now  realize  that  the  method  of 
construction  used  will  influence  the  quality  of  a road  very  considerably,  and  they 
are  now  giving  some  attention  to  this  important  feature  instead  of  leaving  it 
entirely  in  the  hands  of  the  contractor  or  his  superintendent.  Many  State  High- 
way Departments  now  prohibit  dumping  material  on  the  subgrade  in  order  to  avoid 
the  possibility  of  dirty  material,  and  to  eliminate  the  rotigh  subgrade  which  such 
a practice  produces.  The  State  of  Pennsylvania,  for  instance,  in  its  1921 
specifications  will  permit  material  to  be  dumped  on  the  subgrade  only  in  piles 
not  less  than  1,000  feet  apart,  provided  that  500  feet  of  subgrade  in  advance  of 
the  mixer  is  at  all  times  kept  entirely  free  from  obstruction.  The  State  of 
Kansas  permits  material  to  be  dumped  only  on  the  shoulders  of  a road,  and  only 
then  on  planks.  The  States  of  Iowa  and  Illinois  have  somewhat  similar  provision. 
Undoubtedly  in  a short  while  highway  engineers  will  entirely  prohibit  hauling  over 
the  subgrade,  in  order  to  eliminate  the  roughness  and  the  non-uniform  compactness 
resulting  therefrom.  The  tendency  is  for  highway  engineers  to  interest  themselves 
in  the  methods  of  construction  used,  realizing  that  only  by  using  proper  methods 
can  full  benefit  be  obtained  from  the  precautions  they  take  with  respect  to  qual- 
ity of  material. 

Improper  attention  to  maintenance  and  a tendency  to  use  the  same  type 
of  construction  on  all  roads,  has  characterized  highway  engineering  very  largely 
in  the  past.  This  does  not  mean  that  the  value  of  proper  maintenance  or  of 
adapting  various  types  of  construction  to  different  conditions  has  not  been 
realized,  but, if  realized,  proper  steps  have  not  been  taken  to  put  this  realiza- 
tion into  practice.  The  tendency  now  is  to  conserve  existing  investments  in  roads 
by  paying  proper  attention  to  maintenance,  and  to  devote  more  study  to  the  problem 
of  selecting  the  most  economic  type  of  road  for  various  localities.  It  is  un- 
doubtedly true  that  our  trunk  line  system  should  be  constructed  in  the  best  possi- 
ble manner,  and  in  most  localities  the  importance  of  this  system  and  the  amount 
of  traffic  it  will  carry  is  such  as  to  warrant  an  expensive  type  of  road.  It  is 
just  as  true,  however,  that  the  tendency  has  been  to  accept  some  one  type  as  a 


126 


1 


ij- 


"cure-all”,  and  to  use  it  on  all  roads  irrespective  of  cost.  There  is  no  doubt  but 
that  the  majority  of  our  secondary  roads  can  be  made  suitable  for  the  traffic  they 
will  be  called  upon  to  carry  by  means  of  some  of  the  less  expensive  types  of  mater- 
ial, providing  that  proper  attention  is  paid  to  the  location  of  the  road,  the 
profile,  and  preparation  of  the  subgrade.  It  is  fully  recognized  that  the  adoption 
of  a type  of  pavement  on  a heavy  traffic  road  merely  because  of  low  initial  cost 
is  a wrong  policy,  because  the  high  cost  of  maintenance  will  eventually  cause  an 
ultimate  cost  greater  than  that  of  some  other  type  of  greater  first  cost.  Never- 
theless it  is  believed  that  expensive  roads  are  frequently  used,  where  a less  ex- 
pensive type  would  serve  fully  as  well.  Highway  engineers  are  now  devoting  much 
more  thought  and  study  to  the  economics  of  their  problem  than  ever  before.  V/ith 
proper  maintenance  methods  there  is  no  doubt  but  that  a cheaper  type  of  road,  will 
frequently  servo  as  well  as  a more  expensive  type.  At  the  same  time  we  must  not 
overlook  the  fact  that  on  heavy  trunk  line  highways,  the  best  is  none  too  good. 


Considerable  delay  has  been  incurred  during  the  past  two  years,  by  a 
shortage  of  road  building  material.  This  has  led  many  highway  departments  to  cur- 
tail the  building  of  so-called  permanent  roads,  and  to  concentrate  their  efforts 
on  grading,  culverts,  and  bridges.  The  graded  road  bed  has  generally  been  tempor- 
arily surfaced  with  gravel,  to  carry  traffic  for  a season  or  two  until  conditions 
permitted  the  permanent  surfacing  to  be  placed.  On  a heavy  traffic  road,  the 
economies  effected  by  proper  location  and  grading  are  no  doubt  sufficient  to  pay 
for  the  cost  of  the  temporary  gravel  stir  face. 


One  of  the  most  serious  handicaps  to  quantity  production  of  road  during 
the  past  two  years,  has  been  a shortage  of  road  building  material.  Progressive 
highway  departments  have  not  been  content  to  merely  fold  their  hands  and  sit  back 
until  conditions  improved,  but  have  devoted  a large  amount  of  time  and  effort  to 
remedying  the  situation.  This  effort  has  taken  the  form  of  comprehensive  surveys, 
in  conjunction  with  the  State  Geological  Department,  to  locate  suitable  deposits 
of  road  building  material.  In  some  states  these  surveys  have  resulted  in  uncover- 
ing sufficient  deposits  of  suitable  material,  to  construct  a considerable  portion 
of  the  system.  The  laboratories  established  by  these  highway  departments  have 
thus  amply  justified  themselves. 

Contractors  who  are  at  present  being  attracted  to  the  hi^iway  construc- 
tion field  are  a capable  and  keen  lot  of  men,  many  of  them  with  engineering 
training.  The  type  of  contractor  which  modern  hi^iway  construction  is  developing 
is  a far  sighted,  keen,  business  man,  who  realizes  that  the  success  to  be  obtained 
in  this  field  depends  upon  scientific  methods  and  proper  preparation.  Instead  of 
depending  upon  day  to  day  delivery  of  materials  from  the  railroad  with  the 
resultant  chance  for  delay,  the  modern  progressive  highway  contractor  stores  mater- 
ial during  the  inactive  months  in  order  that  the  production  of  roads  can  be  carried 
on  without  delay  during  the  construction  season.  In  this  he  is  being  encouraged 
and  assisted  by  State  Highway  Departments,  most  of  whom,  at  the  present  time,  pay 
for  material  as  it  is  received  at  the  material  yard.  The  result  of  this  coopera- 
tive effort  between  engineers  and  contractors,  is  that  the  yearly  output  of  road 
is  steadily  increasing  per  mixer.  A number  of  instances  of  quantity  production 
of  roads  were  given  in  the  early  part  of  this  thesis,  and,while  it  is  true  that 
they  represent  peak  performances,  it  is  equally  true  that  they  indicate  the  ten- 
dency of  the  time.  A few  years  ago  such  performances  were  entirely  unknown,  even 
as  peak  performances,  and  there  is  no  doubt  but  that  during  the  next  few  years 
they  will  become  common  and  will  be  greatly  surpassed.  These  performances  indicate 
what  we  can  expect  from  the  efficient  contractor  of  tomorrow,  with  his  highly 
trained  and  highly  skilled  organization,  employing  hi$i  class  labor  saving  equip- 
ment. 


127 


Highway  departments  are  gradually  realizing  the  necessity  for  awarding 
contracts  early,  but  as  yet  there  is  still  room  for  a lot  of  improvement.  A 
contractor  who  does  not  receive  his  contract  until  March  or  April  loses  a good 
deal  of  valuable  time  during  the  construction  season  in  getting  ready,  when  that 
time  could  be  much  more  profitably  employed  in  actual  construction.  As  a rule  he 
does  not  order  his  equipment  until  he  has  received  his  contract,  with  the  result 
that  equipment  manufacturers  are  unable  to  supply  the  equipment  without  delay  be- 
cause of  the  large  demand  which  occurs  at  that  particular  season  of  the  year.  The 
manufacture  of  highway  construction  equipment  is  a difficult  problem,  because  the 
demand  for  this  equipment  is  so  variable.  The  heavy  demand  occurs  during  the 
months  of  March,  April  and  May,  with  but  little  demand  during  the  rest  of  the  year, 
If  highway  departments  would  only  realize  this  more  fully,  they  could  increase 
road  production  very  materially  by  awarding  contracts  so  that  the  contractor  would 
have  ample  time  to  secure  his  equipment. 

In  the  past  the  tendency  has  been  to  place  all  the  risk  for  loss  in 
highway  construction  on  the  contractor,  and  the  contracts  and  specifications  have 
been  very  one  sided.  The  tendency  now  is  for  the  state  to  share  with  the  con- 
tractor, the  risk  of  performing  the  vrork.  An  instance  of  this  is  to  be  found  is 
the  Georgia  Highway  Department,  where  Mr.  W.  R.  Heel,  State  Highway  Engineer,  has 
introduced  a new  form  of  contract  known  as  Form  "B".  This  contract  combines  the 
principles  of  cost-plus-a-fixed-sum,  and  competitive  bidding.  The  contractor  in 
submitting  his  bid  divides  it  into  two  parts,  the  estimated  cost  and  the  desired 
compensation.  In  order  to  have  an  incentive  to  keep  down  the  cost,  the  con- 
tractor is  allowed  25  per  cent  of  any  saving  on  the  estimated  cost,  provided  it 
does  not  exceed  50  per  cent  of  the  total  compensation  in  the  proposal.  Should 
the  cost  exceed  the  estimate,  50  per  cent  of  the  excess  is  deducted  from  the  com- 
pensation, with  the  provision  that  the  compensation  must  not  be  reduced  more  than 
75  per  cent.  The  contractor  is,  therefore,  assured  of  at  least  25  per  cent  of 
the  compensation  asked  for  in  his  bid.  The  contract  also  provides  for  a machinery 
and  equipment  rental,  a form  being  provided  which  forms  a part  of  the  contract 
cost  of  work.  This  rental  schedule  is  fixed,  and  only  interest  is  allowed  on  the 
value  of  equipment  plus  a fair  rate  for  depreciation,  insurance,  and  estimated 
repairs.  In  this  way  no  profit  can  be  made  other  than  that  shown  as  compensation, 
and  the  amount  of  profit  depends  upon  the  skill  and  zeal  used  in  prosecuting  the 
work.  The  minimum  compensation  which  a contractor  can  receive  is  25  per  cent  of 
that  asked  for  in  his  bid,  while  the  maximum  is  50  per  cent  in  excess  of  this 
amount.  The  tendency  in  other  states  is  also  toward  sharing  the  risks  with  the 
contractor,  and  this  should  lead  to  decreased  cost  of  construction. 

In  the  past  highway  engineers  have  been  all  too  prone  to  consider  that 
their  problems  were  the  only  important  problems  in  highway  construction,  and  they 
have  not  shown  a tendency  to  cooperate  with  contractors  and  equipment  manufac- 
turers in  a proper  manner.  Contractors  and  equipment  manufacturers  have  been 
looked  upon  as  more  or  less  necessary  evils.  Hi^iway  engineers  should  realize 
that  road  building  is  a cooperative  problem,  and  that  the  manufacturer  of  equip- 
ment and  the  contractor  is  important  and  is  entitled  to  due  consideration.  With- 
out the  equipment  manufacturer  and  the  contractor,  the  highway  engineer  would 
probably  not  make  much  progress.  Happily  at  the  present  time  everybody  concerned 
is  beginning  to  realize  that  road  building  is  a cooperative  proposition.  The 
sooner  this  realization  becomes  general  the  better  it  will  be  for  everybody,  and 
the  sooner  will  our  desire  for  an  adequate  highway  system  be  realized. 


MODERN  METHODS 
0 F 

HIGHWAY  CONSTRUCTION 


COMPARISON  OF  FABRICATED  TRACK  WITH  WOODEN  TIE  TRACK. 


GENERAL  DATA. 


Cost  of  20  pound,  rail  - $2.67  per  cwfc. 

Cost  of  x 4"  straight  railway  spikes  - $4.25  per  cwt. 

Weight  of  -§■"  x 4"  straight  Railway  spikes  - 33.4  lbs.  per  100. 

Cost  of  spikes  $0.0142  each,  or  say  $0,015  on  job. 

Cost  of  splice  plates  and  bolts  - 50f  per  set. 

Weight  of  " " " " 4.86  lbs.  per  set. 

Weight  of  il”  x 2”  track  bolts  - 0.21  lbs.  each,  or  0.63  for  4. 

Weight  of  two  splice  plates  - 4.03  lbs. 

Cost  of  3/8”  x 3"  screw  spikes  - $6.03  per  cwt.  or  1^  each. 

Cost  of  3”  x 6”  x 42”  red  oak  tie  - $0.30  each. 

Cost  of  4”  x 6”  x 42”  pine  tie  - $0.35  each. 

Weight  of  3"  x 6”  x 42”  red  oak  tie  - 20.25  lbs. 

Weight  of  4”  x 6”  x 42"  yellow  pine  tie  - 22.4  lbs. 

Weight  of  4"  x 6"  x 42"  white  pine  tie  - 16.5  lbs. 

Cost  of  forged  steel  joint  clips,  designed  to  eliminate  splice 
plates  and  bolts,  $0.34  each. 

Life  of  rail  and  of  fabricated  track  will  be  taken  at  six  years, 
with  10$  salvage  value,  in  one  case,  and  at  four  years  with 
10$  salvage  value  in  another. 

When  the  life  of  rail  is  taken  at  six  years,  it  will  be  assumed 
that  wooden  ties  are  replaced  in  three  years.  The  wooden 
ties  are  assumed  to  last  four  years,  when  the  life  of  rail 
is  taken  at  this  figure. 

Two  types  of  wooden  tie  track  are  assumed,  namely  soft  wood  ties 
with  4 straight  spikes,  and  hard  wood  ties  with  6 screw 
spikes. 


STRAIGHT  SPIKE  TRACK,  SEVEN  TIES  PER  FIFTEEN  FOOT  SECTION 


$1,879.68 cost  of  rail,  at  $2.67  cwt. 

862.40 cost  of  ties,  at  $0.35 

150.00  cost  of  spikes,  at  $0,015,  4 per  tie. 

352.00  cost  of  splice  plates  and  bolts  at  $0.50  per  set 

$3,244.08 cost  per  mile  of  track 

70.400  lbs weight  of  rail 

55.400  " weight  of  ties,  at  22.5  lbs. 

3,292  « weight  of  spikes,  at  0.334  lbs. 

3,422  ” weight  of  splice  plates  and  bolts  at  4.86  lbs.  per  set. 


132,554  lbs.  or  66.28  tons,  per  mile  of  track. 


COST,  SIX  YEARS  LIFE 


$3,344.06 first  cost. 

1,012.40 new  ties  and.  spikes  at  end  of  3 years. 

515.52 interest  on  rails  and  splices  at  3.85$  for  6 years. 

212.60  interest  on  ties  and  spikes  at  3.5$  for  6 years. 

215.60  replacement  of  "broken  ties,  5$  per  year. 

105.60  replacement  of  lost  splice  plates  and  bolts,  5$  per  year 

1.657.00  freight  on  66.28  tons  at  $0.25  cwt.  for  five  shipments. 

12,672.00 laying  and  removing  at  $0.20  per  foot  twice  a year  for 

6 years. 

662.  80 loading  and  unloading  at  $2.00  per  ton,  five  times. 

$20,297.60 cost  per  mile  for  6 years. 

3,282.93 gioss  cost  per  mile  per  year. 

223. 17 salvage  value  of  rails  and  splices  at  10$ 

3,059.76 net  cost  per  mile  per  year. 

COST,  FOUR  YEARS  LIFE 

$3,244.08 first  cost 

499.59. . .. .1nterest  at  $3.85$  for  4 years. 

147.84 replacement  of  'broken  ties,  5$  per  year. 

105.60 replacement  of  lost  splice  plates  and  bolts,  5$  per  year 

994.20  freight  on  66.28  tons  at  $0.25  cwt.  for  three  shipments. 

8.448.00  laying  and  removing  at  $0.20  per  foot  twice  a year  for 

4 years. 

. 397. 68.  ..  .loading  and  unloading  at  $2.00  per  ton,  three  times. 

$13,  836. 99. . . .cost  per  mile  for  4 years. 

3.459.25. . . .gross  cost  per  mile  per  year. 

223. 17 .. . . salvage  value  of  rails  and  splices  at  10$ 

3. 236.08. . . .net  cost  per  mile  per  year. 

SCREW  SPIKE  TRACK,  EIGHT  OAK  TIES  PER  FIFTEEN  FOOT  SECTION 

$1,879.68 cost  of  rail  at  $2.67  per  cwt. 

844.80 cost  of  3n  x 6”  oak  ties,  at  $0.30 

186.00 cost  of  spikes,  at  $0.01,  6 per  tie,  plus  10$  loss. 

168. 96 .....  cost  of  joint  clips,  at  $0.24 

$3,077.44 cost  per  mile  of  track. 

70,400  lbs ...  .weight  of  rail 

57,024  " weight  of  ties,  at  20.25  lbs. 

2,800  ” ....weight  of  spikes 

2.816  w ....weight  of  joint  clips,  ax  4 lbs. 

133,040  lbs.  or  66.52  tons,  per  mile  of  track. 

COST,  SIX  YEAR  LIFE 

$3,079.44 first  cost 

1,030.80 new  ties  and  spikes  at  end  of  3 years. 

473.23 interest  on  rails  and  clips  at  $3.85$  for  6 years. 

216.47 interest  on  ties  and  spikes  at  3.5$  for  6 years. 

211.20  replacement  of  broken  ties,  5$  per  year. 

1.657.00  freight  on  66.52  tons,  at  $0.25  cwt.  for  5 shipments. 


V1 


665.20  load  and  unload  at  $2.00  per  ton,  five  times. 

1.056.00  assembling  track  at  $0.20  per  foot. 

3.600.00  laying  and  removing  at  $300.00  per  mile,  twice  a year  for 

6 years. 

$11,989.34 cost  per  mile  for  six  years. 

1,998.22 gross  per  mile  per  year. 

204 . 86 salvage  value  of  rails  and  clips  at  10$. 

$ 1,793.36 net  cost  per  mile  per  year. 

COST,  FOUR  YEAR  LIFE 

$ 3,079.44 first  cost. 

474.23  interest  at  3.85$  for  4 years. 

168.96 replacement  of  broken  ties,  5$  per  year. 

994.20  freight  on  66.52  tons,  at  $0.25  cwt.  for  three  shipments. 

399.12 loading  and  unloading,  at  $2.00  per  ton  three  times. 

1.056.00  assembling  track  at  $0.20  per  foot. 

2.400.00  laying  and  removing,  at  $300.00  per  mile  twice  a year  for 

four  years. 

$ 8,571.95 cost  per  mile  for  four  years. 

2,142.99 gross  coot  per  mile  per  year 

204 . 86 salvage  value  of  rails  and  clips  at  10$ 

$ 1,938.13 net  cost  per  mile  per  year. 

SCREW  SPIFF  TRACK,  SEVEN  OAK  TIES  PER  FIFTEEN  FOOT  SECTION 

$1,879.68 cost  of  rail,  at  $2.67  per  cwt. 

739.20 cost  of  3”  x 6n  oak  ties,  at  $0.30 

100.00 cost  of  spikes  at  $0.01,  6 per  tie. 

168.96 cost  of  joint  clips  at  $0.24 

$2, 887. 84 cost  per  mile  of  track 

70,400  lbs. ..  .weight  of  rail. 

49,896  " ....weight  of  ties  at  22.5  lbs. 

1,867  ” ....weight  of  spikes,  four  per  tie. 

2,816  11  . . . .weight  of  joint  clips,  at  4 lbs. 

124,979  lbs.  or  62.5  tons,  per  mile  of  track. 

COST  SIX  YEAR  LIFE. 

$ 2,887.84 first  cost 

839.20  new  ties  and  spikes  at  end  of  3 years. 

473.24  interest  on  rails  and  clips  at  3.85$  for  six  years 

176.23 interest  on  ties  and  spikes  at  3.5$  for  six  years. 

184.80 replacement  of  broken  ties,  5$  per  year. 

1,562.25 freight  on  62.5  tons  at  $0.25  per  cwt.  for  five  shipments. 

625,00 load  and  unload  62.5  tons  at  $2.00  per  ton  five  times. 

1.056.00  assembling  track  at  $0.20  per  foot. 

3.600.00  laying  and  removing  track  at  $300.00  per  mile  twice  a 

year  for  6 years. 

$11,204.56 cost  per  mile  in  six  years. 

$ 1,867.44 gross  cost  per  mile  per  year 

204. 86. ...  salvage  value  of  rails  and  clips  at  10$ 

1,662.  58. ..  .net  cost  per  mile  per  year. 


COST,  FOUR  YEAR  LIFE 


2,887.84 first  cost. 

444.73 interest  at  3.85$  for  four  years. 

147.84 replacement  of  Troken  ties  at  5$  per  year. 

937.35 freight  on  62.5  tons  at  $0.25  per  cwt.  for  three  shipments 

375.00 load  and  unload  62.5  tons  at  $2.00  per  ton,  three  times. 

1.056.00  assembling  track  at  $0.20  per  foot. 

2 . 400 . 00  laying  and  removing  track  at  $300.00  a mile  twice  a year 

' for  four  years. 

8,248.76 cost  per  mile  for  four  years. 

2,062.19 gross  cost  per  mile  per  year. 

204 . 86 salvage  value  of  rails  and  clips  at  10$ 

1,857.33 net  cost  per  mile  per  year. 


LAKEWOOD  PRESSED  STEEL  TIE  TRACK 


COST,  SIX  YEAR  LIFE. 


$ 6,318.40 first  cost. 

1,459.50 interest  at  3.85$  for  six  years. 

1,518.00 freight  on  60.72  tons  at  $0.25  per  cwt.  for  five  shipments. 

607.20 load  and  unload  60.72  tons  at  $2.00  per  ton  five  times. 

2,400.00. ...  .laying  and  removing  track  at  $200.00  per  mile  twice  a year 

for  6 years. 

1, 137. 80 repairs  due  to  straightening  Lent  ties,  etc.  3$  per  year. 

$13,440.40 cost  per  mile  for  six  years. 

$ 2,240.07 gross  cost  per  mile  per  year. 

631 . 84 salvage  value  of  track  at  10$ 

$ 1,608.23 net  cost  per  mile  per  year. 


DOST,  FOUR  YEAR  LISE. 

$ 6,318.40 first  cost. 

973.03 interest  at  3.85$  for  four  years. 

910.80 freight  on  60.72  tons  at  $0.25  per  cwt.  for  three  shipments 

364.32 load  and  unload  60.72  tons  at  $2.00  per  ton  three  times. 

1,600.00 lay  and  remove  track  at  $200.00  per  mile  twice  a year  for 

4 years, 

1 . 157 .30 renai rs  due  to  straightening  bent  ties,  etc.,  3$  per  year. 

$11,303.85 cost  per  mile  for  four  years. 

$ 2,825.96 gross  cost  per  mile  per  year. 

631.84 salvage  value  of  track  at  10$. 

$ 2,194.12 net  cost  per  mile  per  year. 

The  rate  of  interest  is  taken  at  7$,  and  is  figured  on  the  depreciated 
value  at  the  end  of  each  year.  This  results  in  an  average  rate  of  3.85$  where 

the  equipment  has  a 10$  salvage  value,  and  3.5$  where  it  has  no  salvage  value. 
Equipment  having  a salvage  value  at  10$  has  an  average  value  throughout  its  life  of 
100$  plus  10$,  divided  by  2,  or  55$.  Multiplying  the  avex'age  value  of  55$  by  the 


interest  rate  of  7$  gives  an  average  interest  rate  of  3.85$  etc.  This  is  in 
accordance  with  the  methods  recommended  by  the  Associated  General  Contractors. 

Of  the  foregoing  assumptions,  perhaps  that  of  assigning  a six  year  life 
to  the  rail  and  to  the  Lakewood  track  and  replacing  the  ties  at  the  end  of  three 
years  is  most  nearly  correct.  While  there  is  no  experience  to  the  contrary,  it 
is  believed  that  the  assumption  that  wooden  ties  will  last  four  years  when  the 
life  of  the  track  is  taken  at  this  figure  is  somewhat  optimistic. 

When  oak  ties  and  screw  spikes  are  used,  it  is  assumed  that  the  track 
is  not  dismantled  from  year  to  year.  When  soft  wood  ties  and  straight  spikes  are 
used,  it  is  assumed  that  the  track  is  dismantled  at  the  end  of  each  season. 


ITEMS  ENTERING  INTO  COST  OF  HIGHWAY  CONSTRUCTION 


WISCONSIN  STATE  HIGHWAY  DEPARTMENT 
(From  Engineering  News-Record  - April  1,  1920) 


1 - MOVING  EQUIPMENT 

Hauling  from  shed  to  cars 
Loading 

Freight  charges 

Cost  of  unloading 

Moving  to  job 

Lost  time  of  equipment 

Erection  of  camp  including  water  supply 

Transporting  teams  or  trucks 

Return  of  above 

2 - COST  OF  RENTAL  OF  R.  R.  SIDING 

5 - CEMENT,  COST  PER  BARREL.  F.O.B.  CARS  AT 

Number  of  barrels 
Unloading  and  storing 
Hauling  and  covering 

Fire  insurance  on  cement  and  empty  sacks 
Sack  loss  to  5 % 

Freight  return  of  empty  sacks 
Demurrage 

4 - FINE  AGGREGATE 

Number  of  cubic  yards,  includirg  waste 

Average  price  per  cubic  yard,  f.o.b.  pit  or  quarry 

Freight  and  demurrage 

Labor  - unloading 

Hauling  to  job 

(Labor  and  horses) 

Spotting  on  job 
Rehandling  from  stook  pile 

5 - COARSE  AGGREGATE 

Number  of  cubic  yards,  including  waste 

Average  price  per  cubic  yard,  f.o.b.  pit  or  quarry 

Freight  and  demurrage 

Labor  - unloading 

Hauling  to  job 

(Labor  and  horses) 

Spotting  on  job 
Rehandling  from  stock  pile 

6 - SURFACING 

Rolling  subgrade 

Joint  material  delivered  on  the  job 


6  - SURFACING  (Oont’d) 

Labor  mixing  and  placing  concrete  (including  engineer,  firemen,  form 
setters,  fine  graders,  wheelers,  shovelers,  cement  men,  puddlers, 
haling  and  sorting  sacks,  curing,  covering  and  uncovering,  finishers 
water  hoy,  watchmen,  barricade  and  lights) 


Foreman 

days  @ 

men 

days  @ 

men 

days  @ 

man 

days  @ 

men 

days  @ 

PUMPING-  MD  V/ATER  SUPPLY 

(Labor,  connecting  pipe,  setting  pump,  operator,  fuel,  disconnecting 
pipe  and  drilling  well) 

Gasolene,  coal,  oil,  etc. 

Hiring,  shipping  in  men  and  loss  in  running  camp 
Purchase  of  hardware,  lumber,  boots,  etc. 

Rent  of  water,  buildings,  warehouse,  grounds,  etc. 

Building  cross-overs 


7 - BREAKING  AND  MOVING  DIRT  AND  ROOK 

Staking 

Keeping  road  open  to  travel 

Clearing 

Grubbing 

Excavating  earth,  light,  men  and  teams  only 

Excavating  earth,  heavy,  men  and  teams  only 

Excavating  rock,  loose,  men  and  teams  only 

Excavating  rock,  solid,  men  and  teams  only 

Dynamite 

Sloping 

Trimming 

Shoulders 

Ditching 

Moving,  enter  under  No.  1 
Equipment,  etc.,  enter  under  No.  1 

8 - CULVERTS  AND  BRIDGES 

Number  cubic  yards  in  job 

Moving  equipment,  enter  under  No.  1 

Labor,  enter  under  No.  6 

Material,  enter  under  Nos.  3,  4 and  5 

Labor  excavating,  removing  of  old  structures;  building  forms,  removing 
forms,  placing  concrete 
Detours  or  temporary  bridges 
Piling 
Cofferdams 
Expansion  joints 
YYaterproof  ing 
Drains 
Steel 
Lumber 


9 - GUARD  RAILS 

Posts 

Lumber 

Paint 

Hardware 

Creosote 

Labor 

Hauling 

10  - UMFORESEEN  DIFFICULTIES 

Delays  due  to  railroad  embargoes,  strikes  at  pit  or  jobs,  material  plant 
breakdown,  breakdown  of  machinery,  failure  of  water  supply,  bad  weather 
pipe  line  breaks  and  freezing. 

11  - COMPENSATION  AHD  PUBLIC  LIABILITY  INSURANCES  (LABOR  ONLY) 

12  - OVERHEAD 

Per  cent  of  manager’s  yearly  salary 

Per  cent  of  yearly  salary  of  stenographer  and  clerk 

Per  cent  of  yearly  salary  of  material  man  and  timekeeper 

Per  cent  of  yearly  expense  of  manager 

Auto  Mile  at  12^ 

(Railroad  fare,  hotel,  meals) 

Bidding  costs,  conventions,  associations 
Per  cent  of  yearly  office  rent 

Per  cent  of  yearly  office  telephone  and  telegrams 
Per  cent  of  office  supplies,  miscel. 

Corporation  insurance 
Interest  on  borrowed  money 

12  - BOND  COST  (PERSONAL  OR  SURETY ) 

14  - TOTAL  RET  COST  OF  JOB 

15  - PROFIT  FOR  EACH  CLASS,  OF  V70KK.  AS  PAVING.  GRADING.  STC. 

16  - DEPRECIATION  OH  ECUIPMKHT  AS  LISTED  IN  TABLE  II. 


CONSTRUCTION  EQUIPMENT  RENTAL 

SCHEDULE 


A GUIDE  TO  ESTIMATING  CONSTRUCTION  EQUIPMENT  EXPENSE, 
SUBMITTED  BY  THE  COM4  ITT  EE  ON  METHODS  OF  ASSOCIATED 
GENERAL  CONTRACTORS 


A rental  schedule  that  will  furnish  contractors  with  a practical 
means  of  estimating  e quipment  expense  and  determining  adequate  rental 
charges  was  the  objective  sought  by  the  Coirimittee  on  Methods  in  working 
out  a standard  schedule  for  the  Association.  Such  a schedule,  evolved 
from  the  records  and  experience  of  contractors,  manufacturers  and  re- 
builders  of  equipment,  has  been  prepared  by  the  Research  Division  under 
the  direction  of  the  committee  and  approved  by  the  Executive  Board.  It 
is  herewith  presented  for  use  in  determining  rental  charges. 

To  use  the  schedule  with  safety,  it  is  essential  to  -understand 
how  the  amounts  were  obtained,  how  they  are  to  be  applied  and  how  they 
are  limited  for  determining  rental  charges..  Knowing  these  things,  no 
great  difficulty  should  be  found  in  establishing  the  charges  within  the 
bounds  of  practical  accuracy. 

For  the  reasojn  that  arithmetical  averages  as  obtained  from 
available  records  gave  few  rational  values  £ar depreciation  and  repairs, 
such  averages  were  given  less  weight  in  establishing  the  tabular  amounts 
than  the  practical  experience  ox"  contractors.  In  fact,  the  strongest 
evidence  that  these  amount i are  reasonably  safe  and  accurate  lies  in  the 
endorsement  given  them  by  experienced  general  contractors. 

It  may  be  recalled  that  a tentative  draft  of  the  schedule  was 
submitted  to  members  in  the  Weekly  Bulletin  of  July  31.  They  were 
asked  to  criticize  the  amounts  and  offer  suggest  ions.  In  accordance 
with  the  criticism  received,  which  evinced  considerable  study  upon  the 
subject,  some  of  the  tabular  amounts  were  changed.  As  it  new  stands 
the  schedule  represents  the  consensus  of  ppinion  of  many  contractors, 
and  with  the  proper  understanding  of  what  the  percentage  amounts  mean, 
it  should  offer  a safe  means  of  estimating  rental  charges. 

WHAT  THE  VALUES  MEAN. 

The  endless  variation  of  job  conditions,  such  as  topography, 
ground  formation  and  climate,  indicate  how  great  may  be  the  error  of 
any  fixed  equipment  charge  when  applied  to  the  exceptional  job.  But 
having  figures  which  represent  the  mean  of  many  projects,  a starting 
point  exists  for  ascertaining  reasonable  charges  for  the  exceptional 
circumstances.  Figures  given  in  the  standard  schedule  may  be  said  to  show 
equipment  expense  when  machines  are  not  required  to  operate  continuously 
under  either  the  worst  or  the  best  of  operation  strain.  Then  no 
especially  favorable  or  unfavorable  circumstances  attend  a project, 
the  tabular  values  probably  give  the  expense  within  a permissible  error. 

To  eliminate  error  as  far  as  possible  by  permitting  consideration 
- '"d  comparison  of  the  individual  items  that  make  up  equipment  3apper.se , 
the  gross  amounts  are  reduced  to  their  component  parts.  Thus  any  item 


-3- 


of  the  expense  which  is  known  tc  he  unusually  high  in  specific  cases 
may  he  adjusted  iji  the  schedule  to  obtain  a more  appropriate  . en.al 

rate. 

COMPONENT  CF  EXPENSE. 

Seven  items  of  eqnppnent  expense  constittite  the  total  ren-il 
charge  and  require  consideration  in  estimating  a lump  sun  contract  or 
in  determining  fixed  rate  rentals.  An  average  value  lor  eacn  ol  tnese 
items  which  represents  the  expense  of  a general  contractor  s out lit 
as  a whole,  have  been  approved  by  the  executive  board.  The  items  re- 
ferred to  and  their  annual  proportions  of  the  equipment’s  initial  co^t 
are  as  follows: 

SCEEDILE  OF  TYPICAL  RENTAL  COGS 

Items  of  expense  are  expressed  is  per  cents  of  original  capital 
investment  for  equipment  having  a useful  life  of  6 years  and  a salvage 
value  of  25$  of  the  original  cost. 

Per  Cent 

1 pd 

1.  Average  depreciation • 

2 . Equivalent  annual  interest  at  Sqp ^ 

3.  Shop  Repairs * 4 * • • ° 

4.  Field  repairs. 

5.  Storage  and  incidentals * * 

6.  Insurance 

7.  Taxes — — 

Total  annual  expense 32 

Equivalent  expense  on  basis  of  S months  ’ worm- 

iln 

ing  time  per  year 

Rental  rate  per  month. - 

HOYT  TO  OBTAIN  PROP  I©  PERCENTAGE 

These  percentages  and  those  given  in  the. detailed  scheauu. e 
were  determined  according  to  tne  fo^. Rowing  principles. 

The  economical  life  of  a machine  is  considered  to  end  when  res 
value  has  depreciated  to  25$  of  the  original  cost.  The  average  annua, 
depreciation  then-  amounts  to  75#  of  the  initial  cost  diviaed  hy_ the 
number  of  years  it  may  be  expected  to  give  service..  The  initial  cost 
of  a machine  is  represented  by  the  cost  oi  that  machine  e iv,.-e 
the  contractor’s  yard. 

Interest  should  naturally  be  charged  at  the  prevailing  rate. 
This  may  be  computed  in  three  ways: 

1 By  charging  the  prevailing  rate  each  year  on  the  depreciated 
value  of  the  machine. 

2.  By  charging  the  prevailing  rate  each  year  or,  ahe  average 
value  of  the  machine  during  economical  life.  For  eu^le.,  wnen^tne 
salv -ge  rate  value  is  25$  the  average  value  equals  (100$  oy  <-uo, 


' 


-O- 


divided  by  2 = 62g$. 


3.  By  finding  the  proportion  which  the  average  value  is 
of  the  initial  cost  and  charging  this  proportion  of  the  prevailing 
rate  each  year.  This  proportion  is  called  the  equivalent  annual 
interest  and  shows  what  interest  rate  on  original  cost  will  yield 
the  same  interest  as  the  prevailing  rate  when  applied  to  the  depre- 
ciating value  of  the  machine*  This  is  the  method  used  in  the  above 
schedule.  The  average  value  is  62^  of  the  original;  therefore 
the  equivalent  annual  rate  is  62^  of  the  prevailing  rate,  or  6 
of  - 4$. 

Shop  and  field  repairs  are  separated  by  reason  of  a pre- 
vious recommendation  of  the  committee  on  methods  that  field  repairs 
be  considered  a part  of  the  cost  under  cost  plus  contracts  and  shop 
repairs  be  borne  by  the  contractor  and  covered  by  the  fixed  rate  rental 
charge.  This  recommendation  was  made  on  the  ground  that  an  owner  should 
not  be  made  to  pay  the  total  cost,  for  example,  of  re-f  luting  a boiler 
which  may  have  been  burned  out  principally  on  another  owner's  work. 

The  other  items  of  cost  require  no  special  explanation. 

THREE  TYPES  OF  CHANGES 

Owners  of  equipment  find  occasion  to  establish  rental  rate 

as  follows; 


1.  For  a lump  sum  or  unit  price  estimate. 

2.  To  owners  on  cost  plus  work. 

3.  To  others  than  client  owners. 

In  these  instances  charges  should  be  made  as  follows: 

1.  The  rental  charge  or  equipment  expense  for  lump  sum 
work  includes  all  the  items  mentioned  above. 

2.  The  fixed  rate  to  owners  on  cost  plus  work  will  include 
all  but  field  repairs,  if  this  item  is  paid  as  a cost  of  the  work.  To 
the  amount  thus  determined  may  be  added  a service  charge  depending  upon 
the  policy  of  the  contractor,  i.e.  , whether  the  service  of  equipment 

is  included  in  the  profit  fee  or  carried  in  the  rental  charge. 

3.  The  charge  to  persons  other  than  client  owners  includes 
all  of  the  items  of  expense  and  dn  additional  amount  for  profit  or 
payment  for  the  machine's  earning  power. 

A further  consideration  in  each  of  these  cases  is  the  rate 
for  double  shift  work,  where  the  percentages  for  depreciation  c.nd  repairs 
should  be  doubled,  or  nearly  so. 

INDIVIDUAL  JUDGMENT  ESSENTIAL. 

The  committee  desires  to  emphasize  the  fact  that  the  values 
presented  in  the  following  table  should  hot  be  considered  absolute  in 
determining  a rental  charge.  A real  danger  presents  itself  in  using  any 
tabular  percentage  v/ithout  investigating  the  conditions  under  which  the 


- ±- 


equipment  is  to  work.  To  illustrate.  If  the  values  here  given  for 
a standard  gage  shovel  outfit  were  applied  to  such  an  outfit  engaged 
constantly  in  excavating  liard  rock,  the  probability  is  that  the 
charges  allowed  would  not  cover  more  than  half  the  expense.  The 
frequent  dobey  shots  and  the  dropping  of  heavy  boulders  into  cars 
entails  a higher  rate  of  depreciation  and  repairs  than  is  given  in 
the  schedule.  On  she  ether  hand,  if  this  shovel  outfit  were  steadily 
engaged  in  digging  sandy  loam,  the  values  given  in  the  table  would 
probably  cause  the  equipment  charge  to  contain  a fair  per  cent  of 
profit. 

It  is  with  the  understanding  that  individual  judgment  and 
experience  should  adjust  the  tabular  values  to  meet  unusual  condi- 
tions that  this  schedule. is  offered  to  contractors. 

The  component  expenses  incurred  by  the  ownership  and 
maintenance  of  construction  plant  are  expressed  in  this  table  as 
percentages  of  the  initial  cost  for  individual  items. of  equipment. 
They  indicate  the  probable  annual  expense  without  profit  under 
ordinary  job  conditions  and  should  be  included  in  any  lump  sum 
estimate  or  in  determining  time  rate  Pental  charges.  The  salvage 
value  in  all  cases  is  considered  to  be  25$  of  the  initial  cost. 

Total  percentage  amounts  in  the  extreme  right-hand  column 
should  be  applied,  to  the  total  cost  of  a machine  including  charges 
for  transportation  from  the  factory.  This  gives  the  total  annual 
charge  which  for  a lump  sum  contract  covering  a full  season  is  the 
tooal  equipment  expense.  For  determining  a monthiy,i/eekly  or  daily 
rental  rats  the  annual  amount  is  divined  by  tire  number  of  such 
periods  in  the  year  during  which  construction  work  may  be  carried  on. 


- 


-5- 


] 

Items  of  Equipment 

Econo- 

mical 

length 

of 

Life 

Ann'l 

Depre- 

cia- 

tion 

Ann'l 

Shop 

Re- 

pairs 

Ann’l 

Field 

Repairs 

Stor- 
age & 
Inci- 
den- 
tals 

Insur- 

ance 

Taxes 

Total 
Annual 
Chg.$  of 
Initial 
Investin' t 

Yrs. 

i 

d 

i 3 

a. 

fl 

T~ 

d 

i° 

<d 

1° 

Auto -crane 

..  5 

15 

6 

5 

34 

1 

1 

314 

Auto- truck 

25 

20 

20 

•34 

1 

1 

704 

Auto- trailer 

..  5 

15 

6 

5 

34 

1 

1 

31  "2 

Backfiller,  power 

..  4 

18f 

6 

7 

34 

1 

1 

37} 

Ballast  spreader 

..  8 

9f 

6 

4 

34 

1 

1 

25 

Boiler,  upright 

. . 8 

20 

5 

4 

1 

1 

40 

Boiler,  locomotive 

..  8 

9| 

15 

5 

34 

1 

1 

35 

Bucket,  clam  shell 

..  4 

18} 

15 

6 

34 

1 

1 

45} 

Bucket , orange-peel . .... 

. . 4 

18f 

25 

6 

4 

1 

1 

55} 

Bucket,  drag- line... 

..  4 

18} 

12 

3 

34 

1 

1 

39} 

Cars,  steel  dump 

. . 6 

124 

8 

4 

34 

1 

1 

30 

Cars,  wood  dump 

..  5 

15 

7 

3 

34 

1 

1 

304 

Cars,  flat 

..  8 

9§ 

4 

3 

34 

1 

1 

22 

Cars,  hopper 

..  5 

15 

8 

3 

4 

1 

1 

314 

Compres  sor, steam. 

..  7 

10f 

6 

3 

34 

1 

1 

25} 

Compressor,  gasoline 

. . 4 

18} 

6 

7 

3f 

1 

1 

37} 

Compressor,  electric 

..  6 

124 

3 

u* 

3-4 

.h  a. 

24 

Concrete  chutes 

. . 2 

3?4 

15 

15 

34 

1" 

1 

73 

Conveyor,  "belt 

..  2 

37j 

7 

6 

rr  1 

3s 

1 

1 

56 

Conveyor,  Bucket 

..  2 

37-g 

10 

6 

3* 

1 

1 

59 

Crusiher,  rock 

. . 6 

124 

5 

3 

4 

1 

1 

26 

Derrick,  wood 

..  5 

15 

4 

4 

34 

1 

1 

28j 

Derrick,  steel 

. .10 

7? 

4 

3 

34 

1 

1 

20 

Dragline, steam 

. . 6 

124 

9 

8 

3-| 

1 

1 

35 

Dragl ine , gasoline 

..  4 

18} 

10 

10 

34 

1 

1 

44} 

Dragline,  electric 

..  8 

7 

7 

34 

1 

1 

29 

Drill, tunnel  carriage.... 

. . 5 

15 

8 

8 

34 

1 

1 

364 

Drill,  traction. well, ... . 

. . 6 

12i 

7 

10 

34 

1 

1 

35 

Drill,  jack  hammer 

..  4 

18} 

7 

6 

34 

1 

1 

37} 

Drill,  tripod 

..  4 

18} 

7 

10 

3? 

1 

1 

41} 

Engine,  gas 

. . 5 

124 

8 

8 

34 

V 

1 

34 

Engine,  steam 

. .10 

74 

5 

5 

34 

1 

1 

23 

Excavator,  cableway 

..  6 

124 

4 

12 

34 

u 

1 

34 

Excav-tor,  keystone 

..  5 

15 

8 

4 

3? 

1 

1 

32p 

Excav-.tor,  trench 

..  5 

15 

8 

6 

34 

1 

1 

344 

Forms,  steel  concrete.... 

2 

57I 

20 

20 

34 

1 

1 

83 

GriTawcLo if  s j CO.  - on  s o^tci  * • • • • 

..  4 

18f 

12 

6 

34 

1 

1 

42-t 

Graders,  elevating 

...  4 

18} 

15 

7 

\1 

IT 

46p 

Hoist,  steam 

. .10 

^4 

6 

4 

34 

l 

1 

23 

Hoist,  gasoline 

. . 6 

124 

7 

8 

34 

1 

1 

33 

Hoisd,  electric 

. . . 8 

94 

5 

3 

34 

1 

1 

23 

Two  pa 

■ges  of 

chart  - 

- page  #1 

Items  of  Equipment 

Econo- 

mical 

length 

of 

Life 

Ann*  1 
depre- 
cia- 
tion 

Ann'  1 
shop 
re- 
pairs 

Ann’l 

Field 

Re- 

pairs 

Stor- 

age 

& 

Inci-  In- 
den-  sur- 
tals  ance  Taxes 

Total 
Ann’l 
Chg.$ 
of  Ini- 
tial 
Invest. 

Yrs , 

jt. 

J 

df 

P 

* 

fo 

i 

d 

P 

Locomotive  , Indus.  Steam 

, . . 9 

8i 

6 

4 

34 

1 

1 

24 

Locomotive , Indus.  Gas 

. . . 4 

18? 

13 

10 

Si 

1 

1 

47? 

Locomotive,  Indus. Batter 

. . . 4 

18? 

15 

4 

3l 

1 

1 

43? 

Locomotive,  Standard  gage 

. . . 10 

6 

4 

34 

1 

1 

23 

Locomotiveccrane,  steam 

. . . 8 

9~ 

7 

8 

3i 

1 

1 

30 

Locomotive  crane,  elec* 

. ..  8 

9— 

6 

4 

34 

1 

u 

25 

Mixer , steam. 

. . . 5 

15 

12 

4 

34 

1 

1 

3&4 

Mixer,  gasoline 

. . . 4 

18| 

13 

8 

34 

1 

1 

45? 

Mixer,  electric 

. . . 6 

12g 

12 

4 

34 

1 

1 

34 

Mixer,  paving  steam.. 

. . . 5 

15 

13 

4 

34 

1 

1 

37? 

Mixer,  paving  gas 

25 

16 

9 

34 

1 

1 

554 

Motors 

6 

12| 

6 

4 

3? 

1 

1 

28 

Pile  driver,  staaip 

. . . 8 

4 

7 

5 

3f 

1 

1 

27 

Pile  driver,  ttack 

4 

5 

3 

3| 

1 

1 

21 

Pile  hammer,  steam 

...  7 

io| 

7 

3 

1 

1 

26? 

Pipe , galvanized. 

. . . 3 

25 

5 

6 

34 

l: 

1 

41 2 

Plows 

Pneumatic  concrete  machine,,. 

« « • 4 

25 

18f 

15 

20 

10 

8 

3? 

34 

1 

1 

P 

1 

55? 

52? 

Pump,  centrifugal..... 

. . . 8 

9i 

6 

4 

3f 

l 

1 

25 

Pump,  piston . .. 

. . . 6 

1 2? 

7 

5 

34 

1 

1 

30 

Pump,  pulsometer 

. 8 

9f 

2 

4 

3f 

1 

1 

21 

Pump,  Emerson 

. . . 8 

94 

2 

4 

3a 

1 

1 

21 

Rails 

. . . 8 

ok 

•'Z 

5 

3 

l 

1 

23 

Riveter,  air 

...  5 

15 

8 

4 

oX 

1 

1 

32? 

Rock  chauheler 

. . . 6 

12? 

7 

8 

3? 

l 

1 

33 

Roller,  steam  road 

...10 

7k 

5 

3 

34 

l 

1 

21 

Saw  rigs 

...  4 

18? 

10 

15 

3f 

1 

1 

4qi 

'PF 

Scraper,  wheel 

...  3 

25 

8 

4 

si 

1 

1 

42? 

Scraper,  slip 

1 

75 

25 

10 

34 

1 

1 

115J 

Scraper , fresno 

2 

37? 

25 

.■•15 

34 

1 

1 

83 

Shovel,  steam 

6 

12? 

7 

6 

3f 

1 

1 

31 

Shovel , gasol ine 

4 

18? 

9 

7 

3-4 

l 

1 

40? 

Shovel,  electric..... 

7 

10? 

6 

5 

l 

1 

27? 

Switches,  fabricated 

Tower,  steel  hoist 

3 

7 

25 

10? 

3 

3 

3 

4 

3f 

3a 

1 

1 

1 

n 

a. 

36? 

23? 

Tractor  , wheel  gas. 

. . ..  6 

12-1 

9 

5 

34 

l 

1 

32 

Tr-ctor,  caterpillar 

5 

15 

15 

10 

34 

1 

1 

45? 

1 .1  1 

Wagons  , dump ■ 

4 

18? 

17 

3 

?! 

1 

1 

44? 

Pago  ns , haul  i ng 

4 

18? 

12 

3 

n 

1 

39/i. 

Pagon  loaders,  power 

5 

15 

10 

6 

si 

1 

n 

3 &2 

Two  Pages  of  Chart  - Page  -'2 


£ 


* 

N 

A 


3* 


\ 

J 


H: 


£/&£  VX02L3 


3to/v£  70003/. 


3000  7000£2 . 


(//; 


M 


t 

V 

*/OL£S.  * 


< 

► 

asf 

#Tff 


003233 


3307/00  00 
37003  7//00£  /. . 


££C7/O0  00 
3000  7U00£  £. . 


XJ0730/02  £00  00 £ S3O7/O0  0£  700092. 

Srs*T0OsL 

/ve 

0£ ' 
0300. 

O93C0/ 07/00 

29X070 

/ 

/O 

£70073 -fi  X<5  " 

<&-£&' 

2 

20 

02  00X3  - Z "X  £ " 

/ <s-o ' 

3 

S3 

092/.  ' 

4--7&~ 

0 

32 

£0273-  $' 

O'-  9~ 

S' 

20 

£0273  - & 

o-  e>i 

<s 

£ 

£30X73  - <5  "X  /2  * 

7-  £' 

7 

2 

0200X3  -2  "X  /2  " 

/£  - 0 " 

<? 

/O 

£0273-  £ 

/-0-£' 

9 

£ 

3/23.3  — G"X£" 

£-  O" 

/a 

/o 

£0273-&“ 

O - 7x' 

// 

20 

900233 -4- X0.  xjr 

0-3' 

/z 

/£•& 

30/093 

20  0 

/3 

/O* 

30/X33 

3-0  O 

/* 

/& 

£0273- &" 

/"-■*■' 

/£ 

£ 

0200X3-  3 "x  £ 

/£  -O' 

/£ 

2 

0200/<3-3  X <C 

/G-O' 

/7 

2 

0/00X3-  3 "x  /0  " 

/O-ZO” 

/a 

3 

0/90X3-  3'x  S' 

/G-O' 



2 

0200X3- 3" X/O  ' 

/G  - O " 

20 

3 

0200X3-3"X  7" 

/£  - O 

2/ 

3 

02 00X3 -£"X£' 

/*-£' 

22 

/ 

0L00X  - 3 ~X  7 " 

/2-£~ 

/ 73X73  /7.  2/  00O  22  007  70  30/7. 

7X/3  7000 £L.  /.S'  0£3/30£O  0/70007 
0303  03003  70  /-OCO^CT/VsE  03/3073  — 

/?J  L0X3  7/000  0033  007  03OO0TX730O 

■*•  A 

7007  2OCO/0O7/v33  £3  000  7000000 

£OAT  0/.L  T03  700032. 

TU00£2S 

£00  C7£ -0300c.  007-0  3££  0003.  */aa 

£O0  0370/2  0£  n//V/V£4  r/W/“  333  O0V7O.  "*///. 

£O0  033/00  3£  72/0032  £00  23 O0 29  CC/.£T  £070033 S££  093*09 


jrwA-/- 

r^z/v^fij 

0X27 


3000 

C/XX32 

osvj.r 


T0£  Z WO0SO  £SVG/TVJS£/V  /S>/&  CO. 

023\/£2.£T00  0 0/0. 

/D/^^/Zo/S/  <?/=■  TiO'AWZ/. 

£O0 

37  Oi/07  j307O0£S. 

4 L/4/Z.K  "7- /*72?0. 

0£t7~£)  5yV££r^. 


am 


T 


£1 


<0  Vfi 

i '• 


Hi 


FT 


ll  I 

V9 

* J 

FP 


\k-A-  \.6-&~ 


<0 

>1 


4" 


"1  «' 

-'  \n 

? -• 
4-? 

'N  1 

m 

vl 

11 


.r ; 


2>--tr 


M 


\ 


J 

1 

*1 

J 

Hi 


v* 

r 

e> 

«i 

Hi 

f 

"1 

V) 

HI  J 

** 

u 

J 

N 


J I 
i 


>4 

? 

* 

* 

l! 

K° 

*> 

5 

* 

t 

< 


^ l ? 

$ 

I1 


$ 

I 

i 

5 

55 

§ 

$ 

? 

1 

i 

t 

Q 

* 

«j 

l 


l 

Hi 

l 

S 

t 

\ 

Hi 

Q 

S 

§ 

* 

S' 


*> 

>4 

I 

! 

! 

Hi 

* 

<0 

£ 

< 

* 

0 

£ 

HI 

'J 

««l 


5 

I 

5 

I 

Hi 


5 

* 

Nl 

? 


tf 

M 

5 j 

p 

6 


Q 
* 

* * 

8 5f  5 

S W $ 

* 5 1 


k 


$ 

M 


§ 

Hx 

K 

Hi 

1 

J 

§ 


\ 

*N 

I 

01 

*1 

' 

Q 

i JH 
u «3 


1 

jo 

Hj 

'O 

1 

! 


* 
£ 

i 

i 

■4 

i 

n 

55 

h 


200  Cubic  Yard  Storage  Bins 

For  contractors  who  desire  to  build  their  own  bins  this  design  is  suggested 
by  the  Lakewood  Engineering  Company. 

The  sketch,  with  the  bill  of  material,  gives  practically  all  necessary 
information.  (For  bill  of  material  see  reverse  side.) 

Place  the  partition  wall  to  give  proper  ratio  between  sand  and  stone 
for  various  mixes.  Place  1-inch  tie  rods  in  each  system  ol  6"  x 6"  waling 
pieces  6'  0"  apart  horizontally.  Waling  pieces  are  bolted  to  6"  x 6 " verti- 
cals and  to  each  other  with  six  x 131 -j"  bolts  at  each  joint.  Place  Lake- 
wood  tunnel  traps  at  proper  intervals  at  bottom.  Lise  lew  nails  in  the  floor- 
ing. Hold  vertical  sheeting  in  place  by  means  of  2"  x 4"  on  inside  bolted 
through  to  6"  x 6"  wales  on  outside. 


The  Lakewood  Engineering  Company 
Cleveland,  U.  S.  A. 


Bill  of  Material 


Description 

Dimension 

Req’d. 

B.  F’t 

Caps  and  Mudsills 

12"xl2"x8'-0" 

32 

3072 

Posts 

1 2 " x 1 2"x7'-0" 

32 

2688 

Stringers  

2"xl 2"xl4'-0" 

40 

1 1 20 

Side  Wales  

6"x6"xl4'-0" 

30 

1 260 

End  Wales  

6"x6"x9'-0" 

6 

162 

Partition  Wales  

6"x6"x8'-0" 

3 

72 

Flooring  

2"xl  2"x8'-0" 

60 

960 

Sheeting 

2 "x  1 2 "x  1 2'-0  " 

135 

3240 

Verticals  

6"x6"xl3'-2" 

12 

500 

Sheeting  Holder  

2"x4"xl  1 '-6" 

24 

192 

Brace  

2"xl2"x3'-6" 

32 

224 

Bolts 

58"-x13  X" 

216 

310  lb. 

Bolts  ( For  Sheet  H.)  

y2"-xioy2" 

72 

Tie  Rods  

1 "x9'-6" 

27 

702  lb. 

Nails 

201) 

50  lb. 

Nails 

10D 

25  lb. 

■J  19-1 


a ^ 

is 

VS 

* 

% 

"J 

<0 

j*-  g 

t8 

| 

* 

* 

vs 

"1 

♦ 

"n. 

M 

* 

■*4. 

«0 

«0 

•VK}- 

«0 

1!) 

<hm 

$ 

S«Q 

'WO 

XK 

U. 

*3- 

«5 

V 

"> 

Uj 

* 

n- 

Niq 

<K 

* 

Q 

<0 

*) 

3 

i 

*0 

"1 

U 

^«0 

SI 

“5 

*) 

h? 

* 

•{ 

> 

*5 

asp 

<*) 

it 

> 

T 

S) 

V 

't- 

Si 

V* 

> 

1 

a 

O' 

N 

*> 

1 

J 

s 

* 

§ 

a 

<0 


THE  LHKEWOOD  ENGINEERING  CIO.  CZL. EVEL. RND  O.  4-  27-  ZO 


SUBJECT:  D/MCN <5/0 A/ >5  SKETCH  SHOW//VG  V&RIOUS  BRTCHCS ORTFl  SHEET  No  7 8 


t 

"1 

''‘iT 

> 

>1 

MM 

ft) 

kwQ 

3 

* 

OJ 

^-x 

>» 

S 

"i 

M 

«**}- 

p> 

X 

") 

1 

"X 

• 

<0 

ft 

<fc 

ft) 

1 

ft) 

"> 

1 

>x 

1 

ft 

1 

.k 

5 3 

(T 

M 

l1' 

P) 

* 

;-M- 

P) 

irj 

: 

M 

mm 

J 

«o 

^x 

ft: 

M 

"n 

M 

N 

">•* 

«>h{- 

w 

S 

9T} 

•0 

M 

M 

M 

* 

* 

CV) 

r 

«M 

"x 

•*x 

<0 

*0 

ft 

x 

ft 

ft 

ft 

5: 

ft: 

ft: 

ft: 

ft) 

so 

m 

"i 

*• 

ft 

A*d 
A. a 

ft 

O' 

N 

5 3 

M 

M 

ft 

t 

V 

-J 

~<M 

35 

S 

53 

* 

N 

-X 

W 

* 

s 

*Sf 

M 

mm 

«\i 

X 

'X 

£ 

M*| 

?> 

•ft 

i 

'X 

• 

* 

>5 

5 

■0 

l 

MM 

ft 

i 

M 

i 

X 

i 

ft 

ft 

ft) 

1 

•0 

l k 

ft. 

jc  3 
Vj  ft 

O' 

m 

h- 

ft 

5: 

Mx}. 

ft 

•ihj. 

j 

ftj 

N 

MM 

IT) 

<\J 

5C 

> 

> 

V 

’*'x 

MM 

MM 

s 

•J 

M 

W 

ft 

ft 

ft 

ft 

II 

ft 

1 

ft 

■>x 

>x 

l 

*x 

X 

ft) 

ft) 

ft) 

i 

55 

ft 

ft 

ft: 

ft: 

ft 

<S) 

ft) 

ft) 

* 

\s 

it  k 

ft 

O' 

5ei 

ft 

M 

8 

c 

Vj 

( 

5 

i 

ig 

-4 

k 

S 

1 

?o 

« 

<« 

|X 

Mx 

s 

ft1 

W)k 

M 

•i 

X 

M 

<a 

Mx 

V9 

«a 

X 

Qm 

Ji 

ifti 

«6 

ft= 

O' 

>£ 

>x 

u_ 

i? 

Ri 

*)k 

N 

N 

"V 

p> 

O' 

N 

X 

k 2 
*n 

M 

<■ 

d 

N 

N 

•ft 

u X 

go 

rJ 

oi 

") 

d 

M 

«) 

f 

M 

5 

o-’ 

M 

to 

«» 

M 

O' 

•d 

O' 

0 

s 

i k 
-V..v 

•ft 

M 

O' 

M 

fx 

p) 

\ 

N 

N 


* 


I 


«! 


0 

K k 


t 

") 

">kH- 

'H'O- 

p> 

J 

*1 

v. 

MM 

ft)W0 

p» 

M 

*: 

•^X 

M 

N 

») 

M 

M 

M 

p) 

M 

X 

'JN 

mVi 

s 

ft) 

ft 

ft: 

ft) 

-iki 

i 

V) 

? 

m 

-g- 

^«V| 

if) 

t 

■>x 

1 

<0 

ft 

a: 

(Q 

vS 

VJ- 

83 

ft) 

M 

O' 

OJ 

«) 

* 


d 

u 

1 

t 

>»j 

j 

xj 

¥ 


CL-ZVEL-RNO  O.  +-S7-2& 


z 

i 

J 

1 

K 

0 

u. 

0 

0 

z 

I 

£ 

0 

5 

z 

h 

| 

< 

0 

<0 

0 

£ 

“ 

J 

< 

£ 

l 

s 

£ 

K 

lb 

0 

0 

e 

</> 

h 

z 

6 

z 

0 

z 

1- 

0 

0 

0 

E 

X 

0 

0. 

0 

{- 

>• 

a 

0 

0 

7 

i 

t 

% 

z 

0 

E 

5 

3 

in 

a 

z 

z 

0 

•1 

0 

I 

0 

z 

0 

s 

u 

E 

u 

z 

0 

0 

z 

E 

E 

0 

u. 

u 

0 

0 

0 

u 

H 

0 

10 

, * 

H 
• * 

E o 

X U 

i 2 
0 0 
5 E 
{ g“ 

0 * E 0 
S E ^ 

5 g 0 2 

SS*I 

..  I*  ? 0 

o « 9-  2 

0 0 U E 
h w E u 

*52  5 
*88* 
mM 

1 i j j 

5 K P £ 
» o 3 r 

w fc.  y 0 
E J)  £ 
*■  _ to 

■- « S « 

5 

s 

N 

= 

< 

•i 

- 

« 

“ 

MI 


m 


syy/ooL 


/OssLiP/yop/OW. 


/4  "O/P.  <r/yjr-  /Po/V  C/-///-/-2Q  tpspo  yy/vesL. 


Z±  "p/p.  PXLS-**  TO  SS  CPP30/V-//2PT  TP2PT2D 


PSOPSTPl  - xnvcv  y SP3/-2  /PQ/V 


32PP//VG  SOX  


S/VO  S/LL-  S‘ "-<Z4LB.  CPP/V/VSL 


OS/VTSP  S/LL-  P“-  tS^L-S-  CPP/V/V3/- 


■C/SSSP  PL.P7S 


OPPWPSPD-  LTPSP  STSjSL. 


" 0.0.  -g±‘p./-/ 


■" O// ?.  /? oo  


V//P<5  - 2^  "o.  O.  -P-  "P./P. 


3PTC/V  SOX  OS 


i 7 " 

*-/§ 


CX7/?  o 7V?/r^  /g-O"  /•7//V//*f£//*C 


8-zf 


/?PO.  CL/PYP  ■ 


\72PSj  \7PPl 


24  -r<?r 


T//£  C/^X^WOO/D  o/VC/A/33  &//V  & CO. 

C/eve  /<*f7c/  O/7/0.  -M-  » 

P2PVY  TYPE  3 PTC//  3 OX  CPP- 3200  CPPY. 

TO/?  C/P3/4 Y/ /VC  TWO  OP  TWO  37  CO. TT  3P7TC/4  30X33. 


/vo  v/f/*r  a 0/r  - / 7 * o. 


Method  for  Direct  Charging  of  Paving 
Mixer  as  Applied  to  City 
Street  Construction 


Sand  and  Stone  are  hauled  to  street  intersections 
and  handled  into  small  portable  bin  with  clamshell 
bucket.  Bucket  elevator  or  belt  conveyor 
may  also  be  used. 


Each  box  is  loaded  from  the  bin  with  the  exact 
amount  of  sand  and  stone  for  one  batch  for  the 
paving  mixer.  Cement  is  placed  in  separate  com- 
partment. Two  boxes  are  carried  on  each  car.  The 
train  is  pulled  by  a small  gasoline  locomotive. 


Double  track  is  laid  on  subgrade  to  mixer.  Loaded 
batch  boxes  are  hauled  to  mixer  on  inside  track. 
Batch  transfer  uses  weight  of  descending  skip  of 
paver  to  raise  box  from  car.  Box  is  swung  over  skip 
and  dumped.  Empty  box  is  swung  back  and  lowered 
onto  car  as  skip  is  raised  to  discharge  materials 
into  drum. 


Car  and  empty  batch  boxes  are  pushed  onto 
‘‘transfer  track”  and  moved  over 
to  outside  track. 


The  “transfer  track”  is  made  up  of  two  short  pieces 
of  rail  carried  at  the  proper  gauge  on  angles.  Four 
rollers  on  these  angles,  run  in  channels,  and  allow 
the  transfer  to  be  easily  moved  from  one  track  to 
the  other. 


The  “track  transfer”  is  mounted  on  a wood  frame, 
which  can  be  picked  up  and  moved  as 
the  concreting  advances. 


The  Lakewood  Engineering  Co.,  Cleveland,  Ohio,  U.  S.  A. 


Specification  Sheet  No.  P.  I. 
The  Lakewood  Engineering  Co. 
Cleveland,  U.  S.  A. 


The  Lakewood -Burton  Locomotive 

3'A  and  6 Ton 


The  most  satisfactory 
motive  power  for  narrow 
gauge  railway  haulage  in 
every  industry,  in  highway  and 
general  building  construction, 
quarries,  plantations,  logging, 
brick  and  clay  plants,  sand  and 
gravel  pits,  and  industrial  plants 
of  every  description. 

The  Burton  Locomotive  has 
been  developed  to  its  present 
perfection  through  many  years 
of  active  service  in  these  va- 
rious fields  of  usefulness.  It 
combines  simplicity  of  con- 
struction, flexibility  of  operation,  and 
economy  of  performance. 


Friction  Disc  Assembly 


Briefly,  it  consists  of  a power  plant 
mounted  on  a rigid  cast  frame,  carried 
on  four  flanged  wheels  set  to  a 
short  wheelbase  so  that  sharp 
curves  may  be  easily  negotiated. 

Power  is  transmitted  from  the 
engine  to  the  track  wheel 
means  of  a friction  disc 
roller  chains,  eliminating  all  spur 
and  bevelled  gears,  friction 


clutches,  and  other  complicated  parts. 
This  system  of  transmission  enables 
the  Burton  Locomotive  to  operate  with 
load  in  either  direction  at  equal  speeds 
and  with  equal  efficiency.  Operating 
speeds  range  from  21  2 to  10  miles  per 
hour. 

Ma  gneto  ignition,  radiator  cooling 
system,  fuel  tanks  with  ample  capacity 
for  a full  day’s  run,  sand  box,  link  and 
pin  couplers  adjustable  to  suit  various 
heights  of  cars,  are  other  features. 


Brakes  applied  to  all  four  wheels, 
controlled  by  a lever  at  the  operator’s 


Frame  Assembly 


Jack  Shaft  Assembly 


hand,  have  sufficient  power  to  lock  all 
wheels  instantly  in  case  of  emergency. 

A winding  drum  to  carry  steel  cable 
is  furnished  when  desired,  for  the  pur- 
pose of  snubbing  cars,  or  for  assisting 
in  hauling 
up  heavy 
inclines. 


T r a c k 
gauge  is  op- 
tional. Can 
be  furnish- 
ed in  gauges 
of  18,24,30, 
36,  42  and 
50} 9 in. 


Front  View 


Axle  Assembly 


SPECIFICATIONS 


Size 3 Ton. 

Size  of  Motor 4 Cyl.,  334  x 5. 

Horse  Power: 23  at  1000  R.P.M. 

Ignition: Bosch  High  Tension  Magneto. 

Fuel: Gasoline. 


Starting  and  Lighting: Two  Unit  single  wire  system. 

Electrical  Equipment  (Extra) Adjustable  search  lights,  front  and 

rear,  Klaxon  Horn. 

Wheels: Steel,  pressed  and  keyed  on  axles; 

18"  diam. 


Axles: 334"  diam.  high  carbon  steel,  carried 

on  Hyatt  Bearings,  supported  by 
Spring  Pedestals. 

Drive: Friction  disc  drive  by  chains  to  jack 

shaft  and  from  jack  shaft  by  chains 
to  both  axles. 

Friction  Disc: Cast  Iron,  23"  diam. 

Spur  Friction: Tarred  Fibre,  22"  diam.  Shaft  carried 

on  Hy  att  Heavy  Duty  Bearings. 

Drive  Chains: Steel  Roller,  34"  Roller,  1 34 " Pitch. 

W7heel  Base: 39". 


Draw  Bar  Pull  at  5 Miles  per  hour: 

Track  Gauge: 

Length: 

Height: 

Width : 

Weight: 

Brakes : 

Cab: 

Gasoline  Capacity: 

Gasoline  Consumption: 


1400  lbs. 

Optional  18  to  5 G 3.4  v- 
.10'  5". 

Regular  with  cab  6'  2",  without  cab 
4'  9". 

24"  Gauge,  49" 

.7000  lbs. 

On  all  four  wheels. 

Metal  with  side  curtains.  Extra  for 
all-metal  hood. 

20  Gallons. 

Average  conditions,  5 gal.  in  10  hrs. 


6 Ton. 

4 Cyl. , 4 34  x 6. 

46  at  1000  R.P.M. 

Bosch  High  Tension  Magneto. 

Gasoline. 

Two  Unit  single  wire  system. 

Adjustable  search  lights,  front  and 
rear,  Klaxon  Horn. 

Steel,  pressed  and  keyed  on  axies; 
18"  diam. 

334 " diam.  high  carbon  steel,  heat 
treated,  carried  on  Hyatt  Bearings, 
supported  by  Spring  Pedestals. 

Friction  disc  drive  by  chains  to  jack 
shaft  and  from  jack  shaft  by  chains 
to  both  axles. 

Cast  Iron  30”  diam. 

Tarred  Fibre,  2834"  diam.  Shaft  carried 
on  Hyatt  Heavy  Duty  Bearings. 

Steel  Roller,  1"  Roller,  1 34 " Pitch. 

4834". 

2400  lbs. 

Optional,  18  to  5 6 34  "• 

12'  5". 

Regular  6'  3J4",  Special  Construction 
5'  3". 

24"  Gauge,  5534"- 

12000  lbs. 

On  all  four  wheels. 

Metal  with  side  curtains,  Extra  for 
all-metal  hood. 

20  Gallons. 

Average  conditions,  9 gal.  in  10  hours. 


Instructions  for  Using 
The  Lakewood  Subgrader 


The  Lakewood  Engineering  Company 

Cleveland  U.  S.  A. 


October  1920 


Be  Sure  You  Understand  Instructions 
Fully  Before  Using  Subgrader 


The  purpose  of  the  Subgrader  is  to  finish  the 
subgrade  after  the  rough  grading  has  been 
completed. 

The  use  of  the  Subgrader  is  practical  only 
where  materials  are  not  hauled  over  the  fin- 
ished subgrade. 

The  Subgrader  consists  of  cross-timbers  on 
the  under  side  of  which  is  a series  of  steel 
blades  bolted  to  angles.  The  arrangement  of 
the  angles  to  which  these  blades  are  attached 
for  the  various  widths  is  shown  by  the  dia- 
gram on  the  opposite  page. 


How  the  Subgrader  is  Shipped 

The  Subgrader  is  shipped  with  the  angles, 
which  carry  the  blades,  in  place. 

The  following  items  are  shipped  separately: 
One  pulling  cable,  two  hooks,  thimble  in  bight. 
One  turntable  foot  and  stem. 

Four  wheels  with  a grease  cup  screwed  in  each. 
Blade  angles — which  with  those  shipped  bolted 
to  the  frame  of  subgrader  make  up  the  full 
number  for  the  22-ft.  subgrader,  or  a total 
of  6 long  and  6 short  angles. 


The  frame  is  shipped  with  the  necessary  blade  angles  bolted  in  position,  and  the 
compensating  spring  for  the  turntable  in  place.  Upon  receipt  of  the  machine,  the 
blades  are  bolted  to  the  angles,  the  turntable  assembled  and  put  on,  and  wheels,  axles, 
quadrants  and  levers  attached  to  each  end  as  shown  in  the  other  photographs. 


One  set  of  angles  and  two  sets  of  cutting 
blades  for  the  maximum  width  machine,  (for 
a road  22-feet  wide)  are  furnished  with  each 
Subgrader.  Phis  makes  it  possible  to  change 
the  width  of  the  machine  by  obtaining  only 
the  necessary  cross-timbers.  As  there  are  al- 
ways two  sets  of  blades  available,  one  can  be 
sharpened  while  the  other  is  in  use. 

The  machine  is  mounted  on  rollersand  travels 
on  the  forms  set  on  both  sides  of  the  road 
to  contain  the  road  material  or  as  a mold  for 
the  concrete.  The  axles  for  the  rollers  are  made 
with  an  eccentric  bend,  so  that  by  slightly 
rotating  the  axles  the  rollers  are  either  lowered 
or  raised  in  relation  to  the  balance  of  the  ma- 
chine. Varying  depths  of  cut  are  so  provided. 

I he  adjustment  is  made  by  levers  held  in 
position  by  pins  set  in  holes  on  a quadrant. 


Bolts  and  washers  for  fastening  extra  angles 
to  frame.  (2  bolts  and  2 washers  for  each 
extra  short  angle,  and  3 bolts  and  3 washers 
for  each  long  angle). 

One  turntable  lever,  with  bolts  inserted. 

Four  bundles  containing  3 short  blades  each, 
with  bolts  inserted  for  fastening  blades  to 
angles. 

Six  bundles,  each  containing  2 long  blades 
with  bolts  inserted  for  fastening  to  angles. 

One  bundle,  containing  both  end  assemblies 
of  quadrants,  levers,  and  axles,  complete, 
with  pins  wired  in  place. 

One  assembly  of  links  and  levers  for  operat- 
ing turntable,  with  all  bolts  in  place. 

Receiving  the  Machine 

Upon  receipt  of  the  machine,  the  shipment 

should  be  checked  to  see  that  all  the  items  as 


r he  Lakewood  Engineering  Com  pain 
Cleveland , U.  S.  A. 


9 


f=T. : 


/O  f=T. 


Diagram  of  Arrangement 
of  Blade  Angles 
for 

Various  Widths  of 
Subgraders 

Blade  angles  and  two  complete  sets  of  blades 
for  the  22-ft.  machine  are  furnished  with  each 
subgrader,  regardless  of  width. 

The  angles  required  for  the  particular  width  of 
machine  ordered  are  shipped  bolted  in  place  on 
the  frame.  The  extra  angles  not  required  by  such 
width  are  shipped  separately  as  are  all  the  blades. 

There  should  be  six  long  and  six  short  angles, 
and  twelve  long  and  twelve  short  blades  with 
each  subgrader  shipment. 

The  machine  can  be  changed  from  any  width 
to  any  other  width  up  to  and  including  22  feet  by 
obtaining  only  the  cross  timbers. 

When  changing  the  width  of  the  machine,  the 
bolt  holes  shown  in  black  on  this  diagram  should 
be  used  for  fastening  the  angles  to  the  frame. 


The  Lakeivood  Engineering  Company 

Cleveland , U.  S.  A. 


listed  on  the  bill  of  lading  have  been  received 
in  good  condition.  Should  any  part  be  missing 
or  damaged,  the  shortage  or  damage  should  be 
noted  on  the  expense  bill  by  the  freight  agent 
before  the  shipment  is  accepted.  Immediate 
steps  should  be  taken  to  file  claim  against  the 
railroad  for  the  shortage  or  damage  noted. 

Before  a Subgrader  is  delivered  to  the  rail- 
road, the  shipment  is  carefully  checked  at  the 


Assembly  of  turntable  from  front  of  machine.  The  two  holes  in 
the  ends  of  the  upright  links  permit  adjustment  of  the  lift  of  the 
turntable  for  different  depths  of  subgrade.  The  lower  holes  are 
used  for  subgrades  from  7 to  10  inches  deep,  and  upper  holes  for 
depths  less  than  7 inches. 


factory.  The  railroad  acknowledges  receipt  of 
the  complete  shipment  in  good  condition  as  evi- 
denced by  the  bill  of  lading.  The  Lakewood 
Engineering  Company  can  not,  therefore,  be 
responsible  for  damage  or  shortage  which  occurs 
after  the  shipment  has  passed  out  of  our  control 
into  the  hands  of  the  railroad.  We  do,  how- 
ever, welcome  the  opportunity  of  being 
of  assistance  to  customers  who  have 
hied  claims  against  the  railroad  for 
shortage  or  damage  and  will  do  every- 
thing we  can  to  help  in  such  cases. 

To  do  so,  the  original  expense 
bill,  with  the  freight  agent’s 
notation  of  the  shortage,  must 
be  furnished  us. 


the  side  forms.  There  are  two  sets  of  holes  in  the 
bearings  for  the  axles.  For  subgrade  depths  from 
5 to  8 inches  the  axles  should  be  set  nearer  the 
bottom  of  the  timbers.  For  cuts  of  from  7 to  10 
inches  below  the  side  forms,  these  axles  should 
be  set  so  that  they  are  carried  higher,  which  in 
effect,  lowers  the  frame.  There  are  also  two  sets 
of  holes  for  bolting  the  blades  to  the  angles 
which  permit  additional  adjustment  of  the 
depth  of  cut.  All  working  adjustments  are  made 
by  the  eccentric  levers.  A bolt  should  be  placed 
in  the holeof  thequadrant  forthelowest 
position  to  be  used,  to  prevent  the  possi- 
bi  1 i ty  of  the  Subgrader  cutting  too  deep. 

Attaching  the  Gable 

The  hauling  cable  hooks  to 
the  front  corners  of  the  Sub- 
grader. An  eye  in  the  middle 
of  the  cable  attaches  to  the 
tractor  or  roller.  The  roller 
should  always  be  kept  close  to 
the  center  of  the  road  when 
ing  the  Subgrader.  The  haul- 
cable  as  furnished  allows  the 
Subgrader  to  drag  at  the  proper 
distance  behind  the  roller.  No  at- 
rjuld  be  made  to  shorten  this  hitch. 


puff 

ing 


tempt  sh 


The  photographs  repro- 
duced here  show  clearlv  how 
the  Subgrader  should  be 
assembled. 

Adjustment  for  Depth 
of  Cut 

The  machine  can  be  ad- 
justed for  a subgrade  from  5 to 
1 0 inches  deep  below  the  top  of 


The  turntable  as  seen 
from  rear  of  machine. 


The  Lakewood  Engineering  Company 
Cleveland , U.  S.  A. 


4 


bee 


used 


ade 


\ .1 


her 


av 


light  scarifier 
developed  to 
with  the  sub- 
t willgivegood 
i all  soils.  On 
: or  sandy  soils 
larrow  or  farm 
r may  be  used 
if  a scari- 
pe  is  not 
ble. 


Side  Form  Requirements 

Good  side  forms,  well  staked  and  substan- 
tially supported,  are  required  lor  satisfactory 
operation  of  the  machine. 

On  a concrete  road  at  least  400  feet  of  forms 
should  beset  in  advance  ol  the  concretemixer. 

When  using  the  Subgrader,  the  rough  grade 
should  be  completed  in  ac- 
cordance with  the  specifica- 
tions. The  rough  grade  should 
be  thrown  up  for  the  lull  width 
ol  the  road,  and  from  1 to  2 
inches  high. 

It  will  be  found  cheaper  to  d 
leave  a little  too  much  earth 
than  not  enough.  Too  little 
would  require  bringing  in  more 
earth  as  the  work  progresses, 
or  widening  the  shoulder  alter 
the  pavement  is  finished. 


A light  roller  may  be  used  to  advantage  in 
breaking  up  clods  after  scarifying. 

Running  the  Subgrader  through  the  first 
time  from  1 to  2 inches  high  will  serve  as  a 
marker  to  show  where  there  is  excess  earth  and 
where  low  spots  exist  which  must  be  filled. 

The  Subgrader  leaves  the  earth  it  cuts  in 
two  convenient  windrows  to  be  moved  by  a 
Fresno  or  other  scraper  to  the  low  spots,  or 
wasted.  The  second  cut  should  be  made  with 
the  Subgrader  set  to  cut  to 
within  about  one-half  inch  to 
1 inch  of  the  finished  grade,  and 
the  surplus  earth  again  moved 
to  the  low  places,  il  any  exist. 

II,  alter  the  second  cut,  the 
soil  is  dry,  a light  sprinkling 
with  water  will  give  it  a desir- 
able workability.  Il  the  first 
two  cuts  have  lei t the  grade 
sumewhat  ragged  in  appearance  another  light 
rolling  is  generally  to  be  recommended.  The 
character  and  condition  ol  the  soil  will  deter- 
mine just  how  many  more  cuts  the  Subgrader 
must  make  to  take  off  the  last  inch  or  half  inch 
and  bring  the  grade  down  to  the  exact  profile. 

In  easy,  smooth-cutting  soils  the  third  cut 
only  may  be  necessary,  but  il  there  is  any  tend- 
ency of  the  soil  to  tear,  or  to  be  gouged  out  by 
the  blades,  two  or  three  additional  cuts  will  be 
decidedly  better.  As  a rule  the  final  cut  should 
be  not  more  than  one-eight  ol  an  inch.  That 
is  about  what  is  secured  by  dropping  the  levers 


Operation 

The  subgrade  between  the 
forms  should  be  thoroughly 
scarified  and  the  clods  broken 
before  theSubgrader  is  started. 


the  subgrade  between  the  forms  should  be  thoroughly  scarified 
before  the  Subgrader  is  used. 


5 


The  Lakewood  Engineering  Company 
Cleveland , U.  S.  A. 


Assembly  of  wheels,  quadrants  and  levers  on  left  end  of 
machine.  When  planing  the  subgrade,  the  depth  of  cut  is 
regulated  by  moving  these  levers  one  hole  or  more  for  each 
cut.  It  is  important  when  moving  the  levers  to  move 
them  all  the  same  number  of  holes. 

on  the  quadrants  only  one  hole.  A little  ex- 
perience soon  shows  just  how  many  cuts  are 
required  and  how  deep  each  cut  should  be. 

The  Turntable 

A turntable  is  provided  on  the  Subgrader  tor 
reversing  it  and  turning  it  lengthwise  ot  the 
road  to  allow  the  roller  to  pass.  This  turntable 
is  brought  to  bear  on  the  subgrade  by  using  a 
jack  lever  on  the  front  of  the  machine.  When 
this  lever  is  thrown  over,  the  machine  is  lifted 
clear  of  the  forms  and  may  easily  be  turned. 
A heavy  coil  spring,  as  shown,  makes  it  possi- 
ble for  one  man  to  raise  or  lower  the  machine 
on  this  turntable  with  little  effort. 

On  roads  less  than  16  feet  wide,  there  may 


I he  earth  which  has  been  planed  off  is  used  to  fill 
low  spots  in  the  subgrade.  The  excess  is  then  wasted 
outside  the  forms. 


The  surplus  earth  that  is  planed  off  is  left  in  two 
convenient  windrows  behind  the  machine. 


not  be  room  enough  for  the  roller  to  pass  when 
the  Subgrader  is  turned  lengthwise  in  the  mid- 
dle of  the  road.  In  this  case,  the  Subgrader 
should  be  raised  on  the  turntable,  turned 
lengthwise,  and  4x6  inch  timbers  placed  under 
the  rollers.  The  machine  should  then  be  low- 
ered on  these  timbers,  and  moved  to  the  side 
of  the  road.  Then  raise  the  machine  again  and 
remove  the  timbers  to  give  clearance  for  the 
roller. 

Crowned  Subgrade 

When  the  Subgrader  is  to  be  used  on  a 
crowned  subgrade,  this  crown  as  specified  is 
cut  in  the  cross-timbers  before  the  machine  is 
shipped.  All  the  cutting  edges  of  the  blades 
must  be  kept  the  same  distance  from  the  bot- 


The  finished  subgrade  will  be  to  exact  depth  at  all  points. 


I he  Lakewood  Engineering  Company 
Cleveland,  U.  S.  A. 


6 


The  Subgrader  is  raised  on  the  turntable  by  the  jack  lever  on  the  front  of  the  machine,  and  turned 
lengthwise  of  the  road  to  allow  the  roller  to  pass.  'This  is  easily  done  by  one  man. 


tom  of  the  timbers.  Any  slight  adjustment  of 
the  blades  to  accomplish  this  can  be  made  by 
shimming  under  the  blade  angles. 

Operating  Crew 

Where  the  Subgrader  is  used,  the  subgrading 
gang  should  be  kept  about  a full  day’s  work 
ahead  ot  the  mixer.  This  means  that  forms 
should  be  set  tor  400  feet  in  advance  ot  where 
concrete  is  being  placed,  and  the  subgrade 
completed  for  this  distance. 

The  Subgrader  crew  will  also  do  the  follow- 
ing work: 

1.  Set  steel  forms; 

2.  Take  up  steel  forms  and  carry  ahead  tor 
each  relaying; 


The  timbers  on  which  the  machine  is  rolled  to  one 
side  of  narrow  roads,  to  allow  the  roller  to  pass,  are 
carried  on  the  Subgrader. 


3.  Clean  forms; 

4.  Prepare  concrete  for  curing. 

Thus  one  crew  will  take  care  of  all  the  work 
incident  to  setting  of  forms  and  the  fine  grading 
where  the  Subgrader  is  used.  Efficiency  of  op- 
eration will  be  obtained  only  when  the  organ- 
ization is  made  on  this  basis. 

The  average  crew  for  such  work  will  gener- 
ally consist  of: 

1 Foreman 

1 Roller  engineer 

1 Head  form  setter 

2 Helpers  for  form  setter 

6 Laborers. 


For  crowned  subgrades,  the  crown  is  cut  in  the  timbers. 
All  the  cutting  edges  of  the  blades  must  be  kept  the  same 
distance  from  the  bottom  of  the  timbers.  Small  adjustments 
to  do  this  are  made  by  shimming  under  the  blade  angle. 


7 


The  Lakewood  Engineering  Company 
Cleveland , U.  S.  A. 


wm,  pin?; 


IAKEWOOD  Road 
Plant  operates  in 
wet  as  well  as  in  dry 
weather.  The  two  views 
at  the  left  show  Lake- 
wood  plant  owned  by 
J.  J.  Dunnegan  on  13- 
mile  road  job  in  Illinois. 
Lower  left  picture  shows 
a 1920  Model  Lakewood 
Finisher  used  by  Ross  P. 
Beckstrom  on  the  Cher- 
ry Valley  Road,  near 
Rockford,  Illinois. 


HHHi 


wmmmm 


iaa; 


@e 


-u 


gk 


Better  Steel  Forms 

for 

Concrete  Road  Construction 
Curb  and  Gutter  Work 
Sidewalks,  Culverts 
Fence  Posts,  Walls 
Foundations 


Bulletin  No.  36 


The  Lakewood  Engineering  Co. 


Cleveland,  U.  S.  A. 


LAKEWOOD  METHODS  AND  MACHINES 


Announcing 

Lakewood-Hotchkiss  Steel  Forms 


SINCE  1909  the  Hotchkiss  Metal  Products 
Company  has  been  making  steel  forms  for  all 
kinds  of  concrete  construction.  During  his  experience 
of  over  20  years  as  a contractor,  Mr.  M.  S.  Hotchkiss 
specialized  in  concrete  work.  He  saw  the  need  for 
better  forms— he  realized  the  many  advantages  of 
using  metal  forms— and  from  his  long,  practical  ex- 
perience he  developed  the  steel  forms  here  described. 

In  the  development  of  these  forms  an  ideal  has  been 
kept  in  mind— to  produce  a better  form  that  would 
make  possible  better  concrete  w ork  and  to  produce 
that  form  at  a reasonable  price  to  the  user. 

That  these  ideals  have  been  fulfilled  are  evident  to 
the  many  contractors  who  have  used  these  forms. 

It  is  with  pardonable  pride  that  The  Lakewood 
Engineering  Company  announces  the  Hotchkiss  line 
of  steel  forms— the  result  of  over  20  years  of  contracting 
and  12  years  of  manufacturing  experience. 

Lakewood-Hotchkiss  Steel  Forms  are  offered  as  a 
part  of  the  Lakewood  line  of  general  construction 
and  road  building  equipment,  effective  at  once. 


February  17,  1921 


Lakewood-Hotchkiss  Steel  Forms  for 

Concrete  Roads 


A road  form  serves  three  functions 

First.  It  is  the  mold  which  retains  the 
freshly  poured  concrete  in  place  until  it 
hardens  sufficiently  to  stand  alone; 

Second:  It  acts  as  a templet  to  which  the 

top  of  the  pavement  and  the  subgrade  may 
be  struck  off  or  finished  accurately  to  the 
profile ; and 

Third:  It  must  be  a substantial  support  or 

carrier  for  the  finishing  tool,  whether  it  be 
a hand  strike  off,  or  a machine. 

I p to  a few  years  ago  the  first  two  functions 
were  the  only  ones  fulfilled  by  the  form.  Fin- 
ishing and  subgrading  machines  had  not  been 
invented,  and  the  necessity  for  the  forms  to 
act  as  substantial  rails  to  carry  these  heavy 
machines  did  not  exist.  Since  The  Lakewood 
Engineering  Company  introduced  the  Lake- 
wood  Road  Finishing  Machine,  and  the  Lake- 
wood  Subgrader,  we  have  constantly  been  in- 
terested in  the  design  and  proper  setting  of 


the  new  types  of  road  forms  used  by  con- 
tractors. 

Lakewood  has  constantly  urged  the  need 
for  better  forms,  and  more  care  in  their 
installation. 

Recent  tests  by  the  Office  of  Public  Roads 
at  Washington,  and  by  the  highway  depart- 
ments of  several  states,  have  shown  the  tre- 
mendous importance  of  having  the  wearing 
surface  of  a road  perfectly  smooth,  and  free 
from  waves  or  rough  spots  in  the  surface.  It 
has  been  proven  that  such  defects  are  largely 
responsible  for  the  rapid  breaking  up  of  a 
road  when  traveled  over  by  heavily-loaded, 
fast-traveling  vehicles.  Engineers  are  becom- 
ing, each  year,  more  strict  in  that  clause  of 
their  specifications  which  reads  that  a straight 
edge  shall  be  placed  longitudinally  on  the 
finished  surface  of  a road,  and  the  road  shall 
be  considered  imperfect  if  at  any  point  the 
straight  edge  lies  more  than  one-eighth  or 
one-quarter  of  an  inch  above  the  surface. 


Three  stake  pockets  and  two  intermediate  braces  to  each  10-ft.  section  give  strong, 
rigid  support.  No  rivets  in  top  of  form 


4 


It  used  to  be  general  practice  to  use  some 
suitable  size  of  lumber  for  side  forms.  The 
form  was  used  only  as  a guide  for  the  strike- 
off  member.  Finishing  was  done  by  roller  and 
belt  method,  which  in  no  way  disturbed  the 
forms.  It  was  not  possible,  with  such  finish- 
ing methods,  to  procure  the  perfect  road  sur- 


or  under  a subgrader  roughly  hauled  by  a 
road  roller. 

We  now  offer  the  Lakewood-Hotchkiss 
Road  Form,  as  the  result  of  three  years’  study 
of  what  road  forms  should  be,  to  meet  the 
service  required  in  modern  road  construction. 


Features  of  the  Lakewood-Hotchkiss 
Road  Form 


Lakewood-Hotchkiss  blue  annealed,  high 
carbon  steel  road  forms  are  furnished  in  sec- 
tions 10  ft.  long,  and  in  the  heights  for  road 
thicknesses  of  5,  6,  7,  8 or  9 inches. 


The  distinguishing  feature  of  the  design  is 
that  a somewhat  lighter  metal  has  been  used 
for  the  main  section  of  the  form,  but  this 
section  has  been  reinforced  by  stiffening  mem- 
bers, advantageously  placed.  Each  10-ft. 
section  has  the  top  flange  supported  at  five 
intermediate  points  by  a heavy  stiffening 
iron. 


It  is  only  within  the  last  year  or  two  that 
subgrade  machines  have  been  in  use.  They 
shave  the  subgrade  to  exactly  the  right  depth 
below  the  top  of  the  form,  so  that  the  con- 
crete slab  when  poured  will  have  exactly  the 
right  thickness.  The  contractor  is  assured 
that  he  is  not  pouring  more  cement  than  the 
plan  requires.  The  engineer  is  assured  that 
he  is  getting  the  full  specified  thickness. 


Clip  which  engages  joint  slide  gives  extra  strength 
at  end  of  form  and  prevents  damage 
from  rough  handling 

face  which  may  be  had  with  a finishing 
machine,  which  strikes  off,  tamps  and  belts 
to  the  top  of  the  forms  as  a guide. 


This  principle  is  the  same  as  is  used  in 
bridge  design,  where  light  members  are  riveted 
together  to  form  a strong  truss,  rather  than 
using  one  solid  heavy  section  of  sufficient 
strength  to  carry  the  load. 


There  has  been  a constant  improvement  in 
forms  within  the  last  two  years  to  bring  them 
up  to  the  stiength  and  quality  required  by 
these  new  practices  in  mechanical  finishing 
and  subgrading.  Forms  have  been  made 
heavier.  They  have  been  made  stiffer.  Much 
more  attention  has  been  given  to  seeing  that 
they  rest  solidly  on  the  ground.  Great  care 
has  developed  in  the  way  in  which  they  have 
been  staked  down.  It  is  essential  that  the 
form  will  remain  as  set,  even  under  the  load 
of  a finishing  machine  weighing  3,000  pounds, 


Form  clamped  to  stake  with  locking  wedge  which 
is  a permanent  part  of  the  form 


S °J  form,solidIy  locked  together  with  close- 

hi  tmg  metal  slide  extending  from  bottom 
flange,  up  to  and  under  head  of  form 


Lakewood- Hotchkiss  Road  Forms  also  are 
different  in  that  electric  spot  welding  is  used 
111  ad(litio11  to  riveting  to  fasten  the  various 
members  of  the  form  together. 


Lakewood-Hotchkiss  Forms  are  built  so 
that  any  section  may  be  removed  from  a line 
"I  I < 'rms  set  up  to  allow  passage  of  trucks  or 
-ther  contractors’  tools.  There  is  an  extra 
heavy  slide,  at  the  joint,  which  holds  the 
forms  in  alignment,  both  laterally  and  verti- 
<allv,  and  assures  a smooth  joint  between  the 
forms  over  which  the  finishing  machines  may 
nm.  Ihese  slides  are  extra  heavy,  and  so 
located  as  to  be  accessible  for  driving  with 
hand  hammer  when  setting  up  or  taking  down 
the  forms.  It  is  to  be  noted  that  the  top  of 
tins  slide  accurately  fits  into  the  channel 
shaped  head  of  the  road  form.  It  can  be 
definitely  stated  there  will  be  no  opening  of 
the  forms  at  the  joints  because  of  the  careful 
working  out  of  the  details  of  this  locking 
device. 

There  are  no  rivets  in  the  top  flange  of 
I he  form  to  get  worn  and  loose  under  the 
wheels  of  the  finisher  or  subgrader. 


The  Lakewood-Hotchkiss  Road  Form  has 
a bottom  flange  4 in.  wide,  giving  a large 
bearing  area  on  the  ground.  The  top  flange 
,s  2'j  vvi(lc,  which  is  ample  as  a rail  for 
the  finishing  or  subgrade  machines  The  turn- 
(l°wn  section  of  the  top  is  1?.,  in.  deep,  making 
lor  unsuaui  strength  at  this  point. 


I he  sections  of  form  are  made  from  steel 
especially  milled  to  size  for  each  height  of 
form.  The  rolled  edges  of  the  top  and  bottom 
flanges  are  so  smooth  that  a man  cannot  cut 
hls  hn^ers  " File  handling  the  form.  It  is 
the  form  with  the  velvet  edge. 


lhe  forms  a™  staked  to  the  ground  with 
three  stakes  to  each  I()-ft.  section.  The  stake- 
pockets  have  elliptical  holes  giving  consider- 
able leeway  when  driving  the  stake,  so  that 
it  does  not  disturb  the  alignment  of  the  forms. 
After  the  stake  has  been  driven  until  its  head 
ls  ahout  an  inrh  and  a half  below  the  top  of 
the  form>  so  that  the  stakes  will  not  interfere 
with  the  finishing  machine  wheels,  the  form 
18  clamPed  to  the  stake  by  a heavy  wedge 
member  sliding  in  the  stake  pocket.  This 
wedge  is  heavy  enough  to  allow  driving  with 
a sledge  hammer.  It  has  a quarter-inch  bear- 
,ng.(;1,1  lhe  stak*.  and  cannot  become  bent  or 
.rap,rlly  w,,ni-  T|lese  wedges  may,  however, 

. efs,ly  reI)Iace(l  when  worn,  They  are  held 
' pockets  and  cannot  become  lost  on 


Made  extra  heavy  to  stand  hard  service 
Reinforces  head  of  rail  at  joint 


6 


Lakewood-Hotchkiss  Steel  Forms  for 
Curbs,  Gutters  and  Sidewalks 


The  Lakewood-Hotch- 
kiss method  combines  the 
use  of  a better  form  and 
a better  method,  resulting 
in  more  nearly  perfect  con- 
crete work.  The  design  of 
the  forms  is  such  that  the 
same  side  rails  can  be  used 
for  curb,  gutters,  sidewalks, 
foundations,  culverts,  etc. 
Thus,  with  a compara- 
tively small  investment  in 
Lakewood-Hotchkiss  Steel 
Forms,  a contractor  can 
use  this  equipment  for 
practically  any  kind  of 
work  on  which  he  cares 
to  bid. 

One  of  the  attractive 
features  of  Lakewood- 
Hotchkiss  Steel  Forms  is 
the  simple  locking  device 
which  makes  the  entire 
form  a strong  substantial 
use  of  bolts,  stakes  or 


The  same  side  rails  are  used  for  all 
kinds  construction 

unit  without  the 
braces.  This  is 


accomplished  by  locking 
the  division  plates  to  the 
side  rails  with  a wedge  key, 
as  illustrated. 

That  the  use  of  the 
Lakewood-Hotchkiss  sys- 
tem insures  a more  nearly 
perfect  concrete  and  gives 
an  absolutely  perfect  ex- 
pansion joint  can  be  readily 
appreciated  from  the  fol- 
lowing discussion.  In  the 
first  place  this  system 
allows  the  removal  of  the 
side  rails  and  dividing 
plates  20  minutes  after  the 
concrete  has  been  poured. 

To  employ  the  Lake- 
wood-Hotchkiss system 
successfully  a fairly  dry 
mixture  must  be  used.  As 
it  has  been  generally 
agreed  that  a dry  mix  makes  stronger  con- 
crete than  a wet  one,  this  is  an  advantage. 


Using  a dry  mixture  results  in  a dense  concrete  of  maximum  strength.  The  forms 
may  be  removed  20  minutes  after  pouring 


7 


A perfect  expansion  joint  is  assured  when  the  Lakewood- Hotchkiss  method  is  used. 
The  dividing  plates  are  removed  last 


It  is  also  generally 
agreed  that  a good, 
dry  mix,  when  allow- 
ed at  least  20  minutes 
to  take  initial  set,  is 
stiff  enough  to  stand 
without  support. 

If  this  is  true,  no 
harm  can  result  from 
removing  the  side 
forms  20  or  30  min- 
utes after  pouring. 
Furthermore,  as  the 
concrete  will  stand  up 
when  the  side  rails 


are  removed,  it  is  ab- 
solutely certain  that  the 
concrete  surfaces  will 
not  come  together  when 
the  dividing  plate  is 
withdrawn.  Thus  an 
absolutely  perfect  ex- 
pansion joint  is  bound 
to  result. 


Templates  for  Lakewood-Hotchkiss  forms  can  be  furnished  quickly 
to  meet  any  specifications  for  curb,  gutter  and 
sidewalk  construction 


Being  able  to  remove 
the  forms  quickly,  thus 
getting  maximum  ser- 
vice from  his  equipment, 


This  curb  form  is  typical  of  Lakewood-Hotchkiss  steel  forms  in  that  the 
form  is  a strong,  substantial  unit,  using  no  bolts,  stakes  or  braces 


8 


Lakewood-Hotchkiss  sidewalk  forms  are  held  rigidly  in  place  by  locking  the  dividing 
plates  into  the  side  rails.  Each  square  is  uniform  and 
the  alignment  perfect 


a contractor  using  the  Lakewood-Hotchkiss 
method  reduces  his  investment  in  forms  to 
the  minimum. 

Another  big  advantage  to  the  contractor 
of  Lakewood-Hotchkiss  Forms  is  the  ability 
to  use  the  same  side  rails  for  various  kinds  of 
work.  To  illustrate,  let  us  suppose  that  a 
contractor  has  a supply  of  5-in.  side  rails,  10 
ft.  long  which  he  purchased  for  sidewalk  con- 
struction. After  completing  the  walk  he 
secures  a straight  curb  job,  which  we  will 
suppose  to  be  20  in.  deep,  8 in.  on  the  base, 
and  5 in.  on  top.  To  complete  his  outfit,  the 
contractor  simply  orders  a few  curb  templates 


to  correspond  to  the  cross-section  of  the  curb. 
The  5-in.  side  rails  are  built  up  20  in.  high  and 
securely  locked  into  a strong  substantial  form 
by  the  Lakewood-Hotchkiss  locking  system. 

The  next  job,  we  ll  say,  is  a combined  curb 
and  gutter,  a cross-section  of  which  may  call 
for  a template  15  in.  on  the  back  of  the  curb 
and  10  in.  on  the  face  of  the  gutter.  Using 
the  Lakewood-Hotchkiss  method,  the  con- 
tractor orders  a few  curb  and  gutter  templates 
and  his  outfit  is  again  complete.  Three  of  the 
5-in.  side  rails  make  up  the  back  of  the  form 
and  two  5-in.  rails  give  a 10-in.  gutter  face. 


(Left) — Lakewood-Hotchkiss  forms,  using  6-in.  radius  corners,  to  make  approach  from  street  to 
residence.  (Right)- — Spring  steel  flexible  sections  simplify  complicated  curved 
work  and  eliminate  tedious  sawing  and  fitting 


9 


I.akewood-Hotchkiss  dividing  plates  or  templates  can  be  furnished  quickly  to  meet 
any  specifications.  Several  typical  ones  are  illustrated 


10 


I.akewood-Hotchkiss  forms  lend  themselves  to  all  kinds  of  curb, 
gutter  and  crosswalk  construction 


From  this  it  is  readily  seen  that,  being  able 
to  use  the  same  side  rails  for  various  kinds  of 
work,  the  contractor  using  Lakewood-Hotch- 
kiss  system  has  a minimum  amount  of  money 
tied  up  as  an  investment  in  forms.  In  addi- 
tion, he  has  the  advantage  of  all  the  well 
known  economies  of  using  steel  forms. 

Lakewood-Hotchkiss  side  rails  are  carried 
in  stock  in  4,  5,  6 and  12-in.  sizes.  Dividing 
plates  to  meet  any  specifications  can  be 
shipped  by  express  three  days  after  receipt 
of  order. 

A special  high-carbon  blue  annealed  steel 
is  used  in  all  Lakewood-Hotchkiss  forms, 
giving  a lighter  form  just  as  strong  as  a heavier 


form  of  softer  steel.  And  because  plates  for 
Lakewood-Hotchkiss  forms  are  rolled  to  exact 
size,  there  are  no  sharp,  sheared  edges — the 
forms  can  be  handled  without  danger  of  the 
men  cutting  their  fingers.  All  side  rails  are 
slotted  every  twelve  inches  and  are  fitted  with 
end  connections.  With  this  frequent  slotting 
most  any  condition  can  be  met  by  inserting 
dividing  plates  or  stop  plates  at  any  desired 
point. 

Several  typical  dividing  plates  are  illus- 
trated. When  ordering  dividing  plates,  or 
templates,  as  they  are  sometimes  called, 
kindly  note  the  illustrations  carefully  to  see 
that  your  description  is  as  complete  as  those 
shown. 


Curved  walks  and  intersections  easily  built  the  Lakewood-Hotchkiss  way 


1 1 


Lakewood-Hotchkiss  Steel  Forms  for 
Foundations,  Walls  and  Culverts 


The  Lakewood- 
Hotchkiss  method  of 
wall  construction 
closely  lollows  the 
regular  method  of 
wooden  form  con- 
struction, but  elimi- 
nates all  waste  of 
material  and  labor, 
the  need  for  upright 
supports,  and  fitting 
and  sawing. 

In  wall  construc- 
tion the  standard  10- 
ft.  channel  sections, 

6 or  12  in.  wide, 
are  commonly  used. 

Other  widths  may  be 
used.  To  hold  these  side  rails  accurately  to 
the  width  of  the  wall,  narrow,  locking  tie 
plates  are  inserted  in  the  vertical  slots  in 
the  side  rails. 


The  flanges  of  the 
side  rails  are  punched 
for  inserting  the  pins 
where  necessary. 
This,  however,  is  not 
usually  necessary  ex- 
cept when  three  or 
four  sections  are 
placed  one  above  the 
other  before  filling. 

The  sections  may 
be  assembled  and 
then  lifted  to  position 
or  may  be  assembled 
right  in  place.  The 
slip  tongue  and  sock- 
et connections  permit 
removal  of  any  of  the 
rail  sections  without  interference. 

The  locking  tie  plates  are  made  as  nar- 
row as  practical  and  slightly  tapered  with 
shoulders,  so  that  when  keyed  through  the 


The  same  Lakewood-Hotchkiss  side  rails  as  used 
for  curbs,  gutters,  or  sidewalks  are  used y] 
in  wall  construction 


A fine  job — and  all  the  waste  in  lumber  and  labor  saved  by  using 
Lakewood-Hotchkiss  Steel  Forms 


Perfect  angles  made  easily  and  economically  the  Lakewood-Hotchkiss  way 


tongues  of  the  tie  plates  the  channels  are 
drawn  firmly  against  the  shoulders  of  the 
tie  plates.  Thus  the  whole  form  is  held 
securely  together  and  in  alignment.  The 
taper  allows  the  tie  plate  to  be  easily  with- 
drawn -from  the  concrete. 


placed  holds  the  forms  in  more  perfect  posi- 
tion and  alignment,  without  bolting,  bracing, 
or  otherwise  sustaining  them. 

The  corner  sections  are  uniform  and  are 
made  the  same  width  as  the  channel  rails. 
These  are  so  constructed  that  the  two  ends  of 


Each  section  of  Lakewood-Hotchkiss  forms  is  a unit  in  itself.  The  units 
can  be  lifted  to  position  or  assembled  right  in  place 


Locking  these  forms  with  narrow  tie  plates 
and  pulling  them  horizontally  through  the 
wall  is  new  and  original.  It  surprises  the 
builder  to  see  how  efficient  and  practical  it  is. 
By  this  principle  every  shovel  full  of  concrete 


the  angles  are  brought  up  square  and  fit 
nicely  into  the  intermediate  sections.  They 
are  held  by  slip  tongue  connections,  the  same 
as  the  regular  wall  channel  rails.  These  cor- 
ner sections  are  also  locked  with  the  same 


The  Lakewood-Hotchkiss  principle  is  the  same  for  wall  construction  as  for  curb  and  gutter 
work.  The  same  side  rails  and  method  of  locking  are  used  throughout 


13 


narrow  locking  tie  plates  and  can  also  be 
assembled  and  then  raised  in  position  on  the 
wall. 

To  more  minutely  describe  the  corner  sec- 
tions, the  outside  channel  rails  are  intended 
to  take  up  3 ft.  of  space  on  the  building  line, 
and  the  inside  channels  2 ft.  on  the  inside 
line,  on  a wall  1 ft.  wide.  One  of  the  outside 
rails  is  3 ft.  6 in.  long;  the  other  outside  rail 
3 ft.  0 in.  long.  The  3 -ft.  rail  has  tongues 
on  one  end  w'hich  connect  in  the  vertical  slots 
of  the  other  outside  rail  at  the  3-ft.  point. 
This  makes  a perfect  right  angle.  These  rails 
are  so  slotted,  however,  as  to  easily  provide 
for  an  adjustment  in  the  width  of  the  wall 
when  desired,  without  changing  the  entire 
corner  section. 

To  more  fully  describe  the  working  opera- 
tion of  these  wall  forms,  and  to  show  the  prac- 
tical efficiency  in  actual  use,  suppose  the  first 
section  is  set  in  place.  It  can  be  either  6 in. 
or  12  in.  in  depth.  As  fast  as  the  form  is 
filled  the  next  section  is  raised  in  position, 
resting  on  the  flanges  of  the  section  just  filled. 


It  is  the  same  Lakewood-Hotchkiss  prin- 
ciple of  placing,  filling,  removing  and  replac- 
ing— a rapid,  continuous  operation,  making 
steel  forms  in  every  construction  an  eco- 
nomical proposition. 


To  work  to  best  advantage  for  rapid  con- 
struction you  should  have  intermediate  sec- 
tions of  different  lengths,  so  that  the  forms 
may  be  erected  around  the  entire  building, 
unless  the  building  is  larger  than  your  equip- 


and  remove  the  lower  channels,  at  thesame 
time  pulling  the  narrow  locking  plates  through 
the  wall.  The  channel  sections  thus  removed 
are  ready  for  replacement  on  top  of  the  last 
section  filled.  This  process  is  continued  until 
the  desired  height  is  reached. 


ment  would  care  for.  In  this  case  the  erection 
may  be  carried  to  any  point  in  the  building 
line  and  a stop-plate  locked  in  the  form.  To 
illustrate,  if  the  building  is  36  ft.  x 26  ft.  no 
intermediate  short  sections  would  be  needed 
as  the  corner  sections  would  take  up  6 ft.  of 


14 


the  building  line.  Hence  you  would  require 
three  regular  10-ft.  sections  on  each  side  and 
two  regular  sections  on  each  end.  If  the 
building  is  42  ft.  on  one  side  you  would  need 
three  regular  sections  and  one  6-ft.  section  to 
fill  out  this  space  on  accurate  measurements. 
The  space  may  be  varied  also  by  slipping  in 
flat  plates  where  the  building  line  makes  a 
difference  in  inches.  A little  careful  study  in 
this  connection  will  show  how  nicely  this 
method  can  be  worked  out. 

These  wall  forms  can  be  used  to  good  ad- 
vantage where  the  work  will  permit  of  con- 
veying the  concrete  by  means  of  chutes,  or 
when  portable  scaffolding  arrangements  are 
u sed . 

For  culvert  construction  the  same  side  rails 
are  used  as  in  curb,  gutter,  sidewalk  and  wall 
work,  in  connection  with  the  Lakewood- 
Hotchkiss  collapsible  support.  The  same 
Lakewood-Hotchkiss  method  of  locking  the 
forms  is  also  employed,  the  narrow  locking 


tie  plates  being  pulled  horizontally  through 
the  wall  instead  of  vertically  so  that  concrete 
of  any  consistency  may  be  used.  Header  wall 
connections  are  so  constructed  that  they  will 
connect  perfectly  with  the  throat  walls  and, 
at  the  same  time,  give  header  walls  and 
parapets  parallel  to  the  street.  The  collapsi- 
ble support,  and  other  details,  are  shown  in 
the  line  drawings. 

Post  forms,  also,  are  included  in  the  Lake- 
wood-Hotchkiss line  of  steel  forms.  These 
post  forms  are  adjustable  in  lengths.  Forms 
are  removed  without  disturbing  the  posts 
until  the  concrete  has  set.  Made  in  batteries 
so  that  5 or  10  posts  can  be  poured  at  one 
time.  The  same  form  is  used  to  make  plain 
or  ornamental  posts.  The  posts  can  also  be 
cored  in  the  forming  to  permit  bolting  on  of 
steel  or  wooden  pieces  such  as  guard  rails 
etc.  The  division  plates  are  held  securely  in 
place  by  connecting  with  the  end  plates.  The 
whole  form  is  rigidly  locked  by  wedge-shaped 
steel  keys. 


I'he  Lakewood  Engineering  Company,  Cleveland,  U.  S.  A. 

Branch  Offices 


Atlanta  90]/i  N.  Forsyth  St 

Baltimore  American  Bldg 

Buffalo  256  Main  St 

Chicago  Lumber  Exchange  Bldg 

Cleveland  Racine  Bldg 

Dallas  Sumpter  Bldg 

Des  Moines  Hubbell  Bldg 

Detroit  David  Whitney  Bldg 

Kansas  City  Ry.  Exchange  Bldg 


Memphis  Central  Bank  Bldg. 

Milwaukee  Milwaukee  Athletic  Club  Bldg. 

Minneapolis  529  Second  Ave.  South 

New  York  141  Centre  St. 

Philadelphia  Widencr  Bldg. 

Pittsburgh  Union  Arcade 

Richmond  Times  Dispatch  Bldg. 

San  Francisco  Rialto  Bldg. 


Smith  Booth  Usher  Co.  .. 
Smith-Booth  Lusher  C’o.  . 
Clyde  Equipment  Co.  .... 

Clyde  Equipment  Co 

R.  B.  Everett  & Co 

Waldo  Bros.  & Bond  Co. 


Representati  ues 

50  Fremont  St.,  San  Francisco 

228  Central  Ave.,  Los  Angeles 

16th  and  Lpshire  Ave.,  Portland 

542  First  Ave.  South,  Seattle 

3118  Harrisburg  Blvd.,  Houston,  Tex. 

181  Congress  St.,  Boston,  Mass. 


Patent  Notice 

The  devices  described  in  this  publication  are  protected 
by  patents  and  patent  applications  pending. 


77788-5M-2-21 


1 5 


Bulletin  No.  29-D 
Page  2 


Lakewood  Service  to 
Road  Contractors 

Because  no  two  road  construction  jobs  are 
exactly  alike,  it  is  not  possible  to  say  what  the 
size  or  cost  will  be  of  the  paving  plant  needed 
for  the  work  without  a thorough  study  of  the 
conditions  to  be  met. 

Lakewood  engineers,  specialists  in  paving 
plant  layout  and  operation,  are  at  the  service 
of  the  contractor  who  contemplates  undertak- 
ing a large  job.  Upon  request  they  will  gladly 
assist  and  advise  with  him  in  planning  his  work 
and,  after  a personal  investigation,  will  make 
an  estimate  as  to  the  equipment  needed,  and 
what  the  approximate  cost  of  the  work  will  be 
if  handled  by  the  Lakewood  method. 

This  service  is  given  without  charge  and 
involves  no  obligation  on  the  part  of  the  con- 
tractor. 


/'he  Lakewood  Engineering  Co. 


Index  to  Bulletin  No.29-D 


Lakewood  Service  to  Road  Contractors.  . 2 

About  the  Lakewood  Engineering  Co.  . . 4 

How  Lakewood  Applies  Modern  Manu- 
facturing Methods  to  Road  Construc- 
tion  5,  6 

Unloading  Plant 7,  8,  10  and  1 1 

Hauling  to  Mixer 8,  9 and  12 

Plant  Layouts 10  and  1 1 

Operations  at  Mixer 12,  13  and  16 

Tamping  and  Finishing  Concrete, 

16,  17  and  1 8 

Mixing  at  Central  Plant 18 

Road  Car 20 

Batch  Box  Cars  and  Batch  Boxes 21 

Finishing  Machine 22 

Track  and  Joint  Tie 23 

Road  Track  Details 24 

Paving  Mixer 25,  26,  27,  28,  29  and  30 

Pump  Plant 30 

Batch  Transfer 31 

Subgrading  Machine 32 

Platform  Car 33 

Concrete  Mixers  for  Culverts 33 

Clam  Shell  Buckets 34 

Bulk  Cement 35 

Tunnel  Storage 35 

Tunnel  Traps 35 

Grout  Mixer 36 

Tables 37 

Lakewood  Industrial  Haulage 38 

Lakewood  Construction  Plant 39 

Installation  of  Lakewood  Road  Plant.  . . 40 


Bulletin  No.  2Q-D 
Page  3 


rPhe  Lakewood  Engineering  Co. 


Bulletin  No.  29-D 
Page  4 


About  the  Lakewood  Engineering 

Company 

The  Lakewood  Engineering  Company  was  organized  in 
1896.  The  business  showed  a normal  growth  until  late  in 
1914.  Since  then  the  expansion  ot  the  company  in  the 
development  or  absorption  ol  other  companies  has  been 
rapid. 

The  Duplex  Manufacturing  and  Foundry  Company,  of 
Elyria, Ohio,  was  purchased  to  give  the  Lakewood  Company 
its  own  source  of  castings. 

The  Milwaukee  Concrete  Mixer  Company  became 
associated  with  Lakewood  in  the  early  part  of  1917,  fur- 
nishing, through  its  plant,  additional  facilities  for  the 
manufacture  of  mixers. 

The  Marsh-Capron  Manufacturing  Company,  of  Chicago 
Heights,  manufacturers  of  mixers,  entered  into  a similar 
arrangement  in  1918. 

The  Gabon  Dynamic  Motor  Truck  Company,  of 
Gabon,  Ohio,  was  purchased  outright  in  the  fall  of  1917. 

The  rapid  development  from  a comparatively  small 
business  in  1914  to  millions  in  1919  has  had  as  its  most 
interesting  and  outstanding  fact  the  remarkable  ability 
of  the  personnel  of  the  organization  to  grow  as  fast  as 
the  business. 

Coupled  with  this  rapid  growth  and  unusual  ability  is 
a reputation  for  loyalty  and  whole  heartedness  in  the 
Lakewood  organization  which  is  commented  on  by  all 
visitors.  This  spirit,  we  believe,  encourages  more  satis- 
factory business  relations,  real  co-operation  and  service. 


The  Lakewood  Engineering  Co. 


Bulletin  No.  2q-D 
Page  5 


Foreword 

THE  present  demand  for  hard  surface  roads  is  out  of  all  pro- 
portion to  our  ability  to  satisfy  it.  Engineers  who  must  build 
new  roads,  and  at  the  same  time  maintain  the  old  ones,  are 
confronted  by  the  question  of  how  to  get  the  roads  built 
rather  than  by  the  problem  of  raising  money. 

It  is  estimated  that  it  would  require  1662^  years  to  improve  all 
the  present  mileage  at  the  1909-1915  rate  and  33  years  to  improve 
the  necessary  minimum  of  at  least  20  per  cent. 

Very  evidently  the  business  of  constructing  roads  must  be  put 
on  the  same  quantity  production,  uniform  quality,  cost-reducing 
basis  as  our  other  manufacturing  industries. 

Quantity  and  quality  production  is  possible  in  our  manufac- 
turing plants  because  the  work  is  systematized.  Machines  have 
been  substituted  for  manpower;  each  worker  is  given  definite  tasks 
to  do — day  after  day — and,  by  repeating  these  tasks,  becomes 
highly  efficient.  Every  effort  is  made  to  produce  a large  quantity 
of  uniformly  good  quality  at  the  lowest  possible  cost. 

In  the  manufacturing  plant  raw  material  is  received  and  stored 
in  a warehouse.  This  supply  of  raw  material  may  be  great  enough 
to  keep  the  plant  running  for  a month  or  more  independent  of 
railroad  deliveries.  From  the  warehouse  the  raw  material  is 
moved  to  the  producing  machines,  goes  through  the  manufacturing 
processes  until,  finally,  the  finished  product  is  ready  for  the  user. 

So,  manufacturing  processes  can  really  be  divided  into  four 
operations: 

1.  Receiving  and  storing  raw  material. 

2.  Transporting  raw  material  to  manufacturing  machines. 

3.  M anufacturing. 

4.  Delivery  of  the  finished  product. 

The  principles  on  which  the  operation  of  the  concrete  road  plant 
developed  by  The  Lakewood  Engineering  Company  are  based  are 
very  similar  to  those  which  the  successful  manufacturer  follows. 

Instead  of  pig  iron  and  coke,  the  concrete  road  manufacturer 
has,  as  his  raw  materials,  sand,  stone  and  cement.  These  he  must 
unload  and  store,  providing  large  enough  storage  space  to  make  his 
road  factory  independent  of  irregular  deliveries  of  raw  material. 


The  Lakewood  Engineering  Co. 


Bulletin  No.  29-D 
Page  6 


Instead  of  hauling  pig  iron  and  coke  to  the  cupola,  the  manufac- 
turer of  roads  hauls  sand,  stone  and  cement  and  pumps  water  to 
his  manufacturing  machine — the  concrete  mixer. 

And  as  the  steel  manufacturer  melts  the  iron  and  perfects  his 
finished  product,  so  the  manufacturer  of  roads  puts  sand,  stone, 
cement  and  water  into  the  concrete  mixer  and  produces  his  finished 
product — concrete  road. 

The  fourth  step-  delivery  to  destination — is,  for  the  road  manu- 
facturer, a simple  matter,  as  the  distance  his  product  must  travel, 
is,  at  most,  the  length  of  the  boom  on  the  paving  mixer. 

The  Lakewood  road  manufacturing  plant  involves  the  use  of 
machines  instead  of  manpower.  Quantity  manufacturing  of  roads 
is  made  possible.  Cost  of  handling  and  rehandling  raw  materials 
is  cut  to  the  bone.  Waste  of  materials  during  the  manufacturing 
process  is  eliminated.  Labor  is  made  more  efficient  and  labor 
turnover  reduced.  Uniformity  of  product  is  assured  at  no  extra 
cost.  And  a better  product  results-  -a  denser , smoother , longer-service 
concrete  road. 

Details  of  operation  and  description  of  the  equipment  used  in 
manufacturing  roads  by  means  of  the  Lakewood  system  are  given 
in  the  following  pages. 

It  is  hoped  that  this  foreword  will  help  to  emphasize  the  simi- 
larity of  road  manufacturing  to  the  manufacture  of  any  other  com- 
modity, and  will  help  the  reader  to  visualize  the  application  of 
modern  industrial  efficiency  to  the  road  manufacturing  industry— 
an  industry  in  which  quantity  production  and  uniform  quality  have 
never  before  been  achieved. 

And  because  the  use  of  Lakewood  plant  makes  possible  the 
production  of  good  concrete  roads  in  large  quantity,  in  much  the 
same  way  as  our  modern  industrial  plants  operate,  we  say  that 
with  Lakewood  plant  the  contractor  matiufactures  concrete  roads. 

The  system  is  easily  applied  to  laying  concrete  bases  for  brick 
or  asphalt  roads. 


The  Lakewood  Engineering  Co. 


Manufacturing  Concrete  Roads 
With  Lakewood  Plant 

(A  Description  of  the  Method  Employed) 


Bulletin  No.  29-D 
Page  7 


The  manufacture  of  concrete  roads  with 
Lakewood  plant  may  he  divided  into  four 
operations:  1 — unloading  the  raw  material 
(sand,  stone  and  cement);  2 — hauling  this 
material  to  the  mixer;  3 — mixing  the  con- 
crete, and  4 — finishing  the  road  surface. 

Applying  the  principles  of  good  factory 
management,  the  unloading  plant  must  be 
able  to  unload  quickly  to  avoid  demurrage 
charges,  store  enough  material  to  make 
the  operation  of  the  plant  independent  of 
railroad  delivery,  and  designed  to  elimi- 
nate waste  and  costly  rehandling. 

Unloading  and 
Storing  Raw 
Material 

Contrary  to  the 
practice  of  stor- 
ing material  on 
the  grade,  the 
Lakewood 
method  involves 
the  use  of  a cen- 
tral unloading 
and  storage 
plant.  Typical 
layouts  that  can 
bevaried  to  meet 
different  require- 
ments are  shown 
on  pages  10  and 
11. 

When  the  layout  shown  on  page  10  is 
used,  gravity  storage  bins  are  placed  at 
intervals  along  the  railroad  siding  with 
narrow  gauge  track  running  under  the 
bins,  past  the  cement  shed  and  thence  to 
the  mixer.  The  material  is  transferred 
from  cars  to  bins,  or  cars  to  stock  piles, 
by  means  of  a clam  shell  bucket  hung 
from  a locomotive  crane. 

Space  for  stock  piles  is  provided,  as  in- 
dicated, to  take  care  of  material  in  excess 
of  the  bin  capacity  and  to  allow  storage 
of  enough  material  to  make  operation  in- 
dependent of  railroad  delivery.  The  stock 


pile  capacity  does  not  have  to  be  so  large 
as  when  hauling  is  done  on  the  sub-grade 
as  only  a few  stock  piles  are  required  and 
the  same  piles  are  used  throughout  the 
job. 

When  bag  cement  is  used  the  bags  are 
transferred  from  the  railroad  cars  to  the 
cement  platform  or  shed  by  hand.  If  bulk 
cement  is  used,  the  cement  platform  is 
unnecessary.  The  bulk  cement  is  received 
in  gondola  cars,  properly  protected  by  a 
tarpaulin  or  tar  paper  housing.  By  replac- 
ing the  cement  shed  with  gravity  bins  and 

fitting  the  bins 
with  removable 
water-tight  cov- 
ers to  permitthe 
entrance  of  the 
clam  shell,  the 
cement  can  be 
unloaded  by  the 
bucket. 

At  this  central 
loading  plant 
sand  and  stone 
are  poured  from 
the  gravity  bins 
into  road  cars 
or  batch  boxes 
having  separate 
and  properly 
pro  po  r t i on  ed 
compartments 
for  sand  and  stone  and  a water-tight  box 
for  cement.  After  a train  is  loaded  with 
sand  and  stone  it  is  moved  past  the  cement 
shed,  where  the  cement  boxes  are  filled. 

Whether  bulk  or  bag  cement  is  used, 
the  cement  boxes  are  filled  at  the  central 
loading  plant,  covered  with  a water-tight 
lid,  and  the  correctly  proportioned  batches 
are  ready  to  be  hauled  to  the  mixer.  As 
no  cement  leaves  the  storage  shed,  ex- 
cept in  the  water-proof  box  in  the  road  car, 
no  sacks  are  taken  out  on  the  grade, 
saving  the  cost  of  taking  care  of  the  sacks. 

As  the  locomotive  crane  is  the  first 


The  Lakewood  Engineering  Co. 


Bullet  hi  No.  29- D 
Page  S 


Clam  shell  bucket  hung  from  crane 
transfers  materials  to  bins  ami  Storage 
piles.  Costly  rehandling  is  avoided. 


equipment  on  the  job,  it  can  be  used  to 
unload  other  machinery.  The  material 
plant  can  be  made  ready  and  operations 
begun  while  grading  is  being  done.  And  as 
soon  as  a part  ol  the  grade  is  finished,  con- 
crete placing  can  be  started. 

Having  a flexible,  large-capacity  plant, 
capable  ot  utilizing  the  entire  length  of 
the  railroad  siding,  the  work  is  made 
practically  independent  of  irregular  mate- 
rial deliveries. 

And  with  this  type  of  plant  practically 
no  hand  labor  is  required  and  rehandling 
of  material  is  reduced  to  a minimum. 


barge  storage  piles  permit  quick  unload- 
ing, and  it  is,  therefore,  possible  to  re- 
lease sand  and  stone  cars  immediately, 
th  us  avoiding  demurrage  charges.  The 
unloading  can  be  done  regardlessof  weath- 
er conditions,  which  is  a decided  advan- 
tage over  the  practice  followed  in  the  past. 
)nce  the  materials  are  unloaded  the  cost  of 
lading  them  into  road  cars  is  practically 
nothing  and  the  loading  is  independent 
of  the  crane.  Furthermore,  no  money  is 
spent  for  hauling  until  the  materials  are 
actually  needed  at  the  mixer.  And  as 
practically  all  of  the  sand  and  stone  can 
be  used  (due  to  having  only  a few  big 
stock  piles)  waste  of  material  is  avoided 
and  aggregates  are  kept  clean. 

The  unloading  plant  shown  in  the  lay- 
out on  page  10  is  for  use  where  bins  are 
used.  The  tunnel  arrangement  shown  on 
page  1 1 is  a variation  to  meet  the  con- 
tractor’s requirements. 

Hauling  Batches  to  the  Mixer 

No  construction  work  is  stopped  so 
completely  by  wet  weather  as  con- 
crete road  work,  when  materials  are 
hauled  on  the  sub-grade  in  wagons 
or  trucks.  Hence,  the  method  ad- 
vocated by  The  Lakewood  Engi- 
neering Company  eliminates  haul- 
ing in  wagons  or  trucks  and  in- 
volves the  use  of  specially  designed 
road  cars  and  narrow  gauge  track, 
as  indicated  by  the  layouts  on 
pages  10  and  1 1 . 

Contractors  usually  endeavor  to 
overcome  the  disadvantages  of 


Work  was  stopped  on  this  road  because  the  grade  was  too  wet  to 
permit  hauling.  Cars  and  track  prevent  such  delays. 


The  Lakewood  Engineering  Co. 


Bulletin  No.  29-D 
Page  9 


Track  can  be  laid  on  shoulder  or  sub-yrade,  thus  giving 
flexible  operation  to  meet  every  condition.  The  center 
picture  shows  a train  operating  in  wet  weather  when 
hauling  over  sub-grade  in  trucks  would  be  impossible. 


hauling  on  the 
grade  in  wet  weather 
by  stocking  sand  and 
gravel  on  the  finished  sub- 
grade as  far  ahead  of  the  mixer 
as  possible.  But  in  doing  this 
the  contractor  is  only  partially  insuring 
a supply  of  the  necessary  materials. 
Seldom  is  cement  stored  in  quantities 
on  the  grade.  Water  is  never  stored  on 
the  grade.  Therefore,  storing  sand  and 
stone,  but  not  storing  cement  and  water, 
does  not,  by  any  means,  free  the  con- 
tractor from  delays  caused  by  lack  of 
material  at  the  mixer.  The  sub-grade  is 
simply  used  as  a place  to  stock  pile  part 
of  the  material.  No  more  wasteful  place 
could  be  chosen  for  a stock  pile. 

To  be  able  to  haul  on  the  grade  with 
wagons  or  trucks  a long  stretch  is  usually 
graded.  Bearing  in  mind  that  the  hauling 
will  have  to  stop  when  rain  comes,  con- 
siderable quantities  of  sand  and  gravel  are 


stocked  on  the  grade  before  concrete  plac- 
ing is  begun.  This  results  in  a loss  of  one 
or  two  months  of  valuable  time  out  of  a 
season,  before  the  actual  laying  of  con- 
crete is  begun. 

By  using  a central  loading  plant,  un- 
loading of  materials  and  the  grading  can 
be  started  simultaneously . And  as  soon  as 


(Continued  on  page  1 2) 


The  Lakewood  Engineering  Co. 


Bulletin  No.  2Q-D 
Page  io 


This  plant  has  the  following  characteristics: 
Single  track  siding;  traveling  crane  having  full 
circle  swing  handling  a clam  shell  bucket;  storage 
bins  for  sand  and  stone  from  which  to  load  narrow 
gauge  cars;  house  in  which  to  store  cement  in 
bags;  narrow  gauge  track  with  passing  siding  on 
sub-grade. 

Stock  piles  should  be  large  enough  to  permit 
operating  the  unloading  plant  for  several  days 
before  hauling  begins.  The  crane  unloads  sand 
and  stone  direct  from  railroad  cars  into  the  bins. 
When  the  bins  are  full  and  the  narrow  gauge  rail- 
way is  not  operating,  the  crane  immediately  un- 
loads from  the  railway  cars  into  the  stock  piles 
and  in  this  way  eliminates  demurrage  charges. 

If,  on  the  other  hand,  the  narrow  gauge  road 
is  operating  when  no  cars  have  been  received  from 
the  railroad,  the  crane  rehandles  material  from 
the  stock  piles  into  the  bins.  Thus  the  unloading 
is  independent  of  the  hauling  and  may  proceed 
regardless  of  weather  conditions  or  time  of  day. 
These  features  make  this  type  of  unloading  plant 
most  economical  when  the  yardage  to  be  handled 
justifies  the  plant  investment. 

Bags  of  cement  are  stored  in  the  cement  house 
or  are  emptied  directly  into  the  road  cars.  Hop- 
pers with  bin  gates  and  measuring  devices  may 
be  used  economically  under  certain  conditions. 

A train  of  cars  is  pushed  under  the  stone  bin 
and  the  stone  compartment  in  each  car  is  filled 
with  that  aggregate.  The  train  is  then  moved  to 


the  sand  bin  and  the  sand  compartments  are 
filled.  The  watertight  cement  compartments  are 
filled  and  the  train  is  ready  to  be  hauled  to  the 
mixer. 

The  locomotive  places  the  loaded  cars  on  the 
track  as  shown.  Cars  are  handled  either  singly 
or  in  pairs  over  the  stub  end  of  the  track  to  the 
mixer.  The  batch  transfer  lifts  the  car  bodies 
and  dumps  them  into  the  mixer  as  described  on 
pages  12  and  13.  The  empties  are  pushed  onto 
the  passing  siding. 

Laying  the  track  on  the  sub-grade  is  not  recom- 
mended. Where  possible  it  should  be  laid  on  the 
she  julder,  as  shown  in  Layout  M-232.  When 
track  is  on  the  subgrade  it  is  necessary  to  move 
the  switch  nearest  the  mixer  two  or  four  times  a 
day.  This  causes  delay. 

I'he  switch  of  the  passing  siding  farthest  from 
the  mixer  should  be  lifted,  at  the  most,  once  a 
day  or,  under  certain  conditions,  every  second  or 
third  day. 

Laying  the  track  on  the  sub-grade  is  necessary 
when  going  over  the  bridges  that  have  to  be 
paved,  through  cuts,  or  in  other  places  where 
there  is  not  sufficient  width  of  shoulder. 

With  a revolving  crane  handling  a 1 -yd.  Lake- 
wood  clam  shell  bucket  for  unloading,  it  is  pos- 
sible to  handle  about  300  cu.  yds.  of  sand  and 
stone  a day.  This  is  sufficient  to  supply,  to  max- 
imum capacity,  a No.  14  E paver. 


The  /.akewood  Engineering  Co. 


Bulletin  No.  29-D 
Page  11 


The  characteristic  features  of  this  plant  are: 
A double  track  siding  on  which  material  cars  are 
received  which  shortens  the  length  of  yard;  a 
movable  derrick  handling  a l^-yard  clam  shell 
bucket;  sand  and  stone  piles  of  very  large  size, 
through  which  is  run  a tunnel; and  a storage  house 
for  bulk  cement;  and  the  use  of  two  concreting 
outfits.  The  bulk  cement  is  unloaded  with  a clam 
shell  bucket  and  lowered  through  hatches  in  the 
roof  of  the  cement  storage  house. 

This  method  of  storing  materials  provides  for 
much  larger  storage  capacity  than  Layout  M-231. 
Sand  and  stone  piles  may  be  accumulated  during 
the  winter,  or  many  months  before  the  work  is 
ready  to  go  ahead.  T his  feature  enables  the  con- 
tractor to  obtain  his  materials  at  a reduced  price 
and  eliminates  shut  down  due  to  irregular  deliver- 
ies. 

The  tunnel  is  built  of  timbers.  A design  will 
be  supplied  upon  request.  The  tunnel  is  pro- 
vided with  bin  gates  or  traps  in  its  roof,  so  that  a 
large  percentage  of  the  stored  materials  will  flow 
by  gravity  through  the  traps.  The  cement  stor- 
age house  has  traps  in  its  floor. 

As  the  trains  of  road  cars  travel  through  the 
tunnel  they  are  loaded  with  sand  and  stone  by 
tripping  the  traps  in  the  roof.  These  traps  are 
spaced  uniformly  so  that  each  car  is  served  by  its 
own  trap,  thereby  reducing  the  need  for  car 
spotting. 

This  plan  shows  how  two  mixers  may  be  used 
on  a typical  road  job  where  the  unloading  plant 
is  located  at  a point  near  the  center  of  the  road 


job.  One  mixer  works  on  a long  haul  toward  the 
unloading  plant,  and  the  other  mixer  works  on  a 
short  haul  away  from  the  unloading  plant.  As 
the  haul  shortens  for  the  first  mixer  the  track  is 
taken  up  and  relaid  ahead  of  the  second  mixer. 
It  is  possible  to  use  two  mixers  in  this  way  when 
the  shoulder  of  the  road  is  wide  enough  to  accom- 
modate the  track.  At  least  4 ft.  of  shoulder  is 
necessary. 

Passing  sidings  for  cars  may  be  laid  on  the  sub- 
grade, as  shown  at  “A”,  or  thrown  over  toward 
the  ditch  or  into  a field  as  at  “B”.  The  arrange- 
ment of  these  passing  sidings  must  in  every  case 
be  determined  by  the  layout  of  the  road  under 
construction. 

Passing  sidings,  as  at  “C”,  must  be  provided  as 
close  to  the  storage  piles  as  possible.  Others 
should  be  laid  along  the  main  road  so  that  out- 
going loaded  trains  may  pass  incoming  empty 
trains. 

This  type  of  plant  can  be  designed  for  larger 
capacities  than  are  possible  with  Layout  M-231, 
and  an  unloading  plant  big  enough  to  take  care 
of  two  mixers  can  be  made  a comparatively  simple 
proposition. 

The  characteristics  of  Layouts  M-231  and 
M-232  are  interchangeable.  The  best  arrange- 
ment of  plant  for  any  job  cannot  be  definitely 
stated  but  should  be  carefully  determined  before 
equipment  is  purchased.  Lakewood  Engineers 
are  always  at  the  customer’s  service  to  assist  in 
studying  conditions  and  designing  suitable  plant 
layouts. 


The  Lakewood  Engineering  Co. 


Bulletin  \No.  2Q-P 
Page  12 


FIG.  1— Bail  Attached  to  Car  Bodv 


a short  part  of  the  road  is  graded  con- 
creting can  he  started.  This  lengthens  the 
working  season  considerably — usually  one 
or  two  months. 

By  starting  the  grading 
and  concrete  placing  at 
the  point  nearest  to  the 
unloading  station,  work 
is  begun  with  the  dif- 
ferent parts  of  the  job 
close  together  and  under 
the  supervision  of  one 
man.  The  mixer  can  start 
operating  as  soon  as  a 
part  of  the  grade  is  fin- 
ished. I he  hauling  will 
not  interfere  with  the 
grading,  nor  with  the  method  employed 
in  grading. 

In  this  way  the  job  is  begun  with  the 
shortest  haul  and  the  easiest  working  con- 


When the  long  haul  is  finally  reached,  the 
track  has  been  thoroughly  imbedded  and 
is  better  able  to  stand  the  long  haul  than 
newly  laid  track.  In  this  way  the  grading 
can  be  completed  immediately  in  front  of 
the  mixer  and  the  grading  and  placing  of 
concrete  can  be  done  simultaneously, 
throughout  the  entire  season.  This  natur- 
ally lengthens  the  working  season  by  be- 
ginning concrete  work  a month  or  two 
earlier  than  usual. 

Bv  not  hauling  over  the  grade  a truer, 
more  even  grade  is  obtained  and  no  mate- 
rial is  wasted  by  filling  up  ruts  caused  by 
hauling.  The  sub-grade,  once  finished, 
needs  no  more  attention. 

The  road  construction  track  can  be  laid 
on  the  shoulder  of  the 
road  wherever  the  shoul- 
der is  at  least  4 ft.  wide. 
This  makes  itunnecessary 
to  move  the  track  as  the 
mixer  moves  forward.  For 
the  same  reason,  where 
there  is  additional  width 
on  the  shoulder,  it  is  best 
to  put  the  passing  track 
outside  of  the  sub-grade. 

By  hauling  in  cars  on 
track,  material  can  be  re- 
ceived and  unloaded  the 
same  day  the  grading  begins.  Concrete 
placing  can  begin  as  soon  as  a part  of  the 
grade  is  finished  and  can  follow  the  grading 


ditions.  Part  of  the  cars  and  track  can  be 
used  for  grading  before  they  are  all  needed 
to  haul  material.  The  haul  increases  as 
the  work  progresses,  so  that  the  contrac- 
tor can  estimate,  in  advance,  how  much 
equipment  and  locomotive  power  he  is 
going  to  need  when  he  gets  the  maximum 
haul.  And  as  concrete  is  laid  during  the 
first  month  of  operation,  the  contractor  is 
entitled  to  a bigger  monthly  estimate, 
thus  simplifying  the  financing  of  the  job. 

There  is  no  necessity  for  laying  a con- 
siderable length  of  track  at  one  time. 


7 he  I.akewood  Engineering  Co. 


FIG.  3 — Batch  Swung  Over  Skip 


Bulletin  No.  29-D 
Page  13 


closely.  Wet  weather  does  not  interfere 
with  hauling  or  placing  concrete,  unless  it 
is  raining  so  hard  as  to  damage  the  surface 
of  the  finished  concrete. 

This  regularity  of  consuming  material 
reduces  rehandling  of  material  to  a mini- 
mum. Many  a job  is  shut  down  because 
of  the  grade  becoming  wet  and  the  con- 
tractor not  caring  to  take  the  chance  of 
ordering  the  rest  of  his  material  when  not 
sure  that  he  would  be  able  to  haul  it. 

Where  hauling  is  done  on  the  grade 
with  wagon  or  with  motor  trucks,  it  is 
always  uncertain  whether  the  unpaved 
earth  will  stand  up  under  the  travel. 
Often  clay  will  make  part  of  the  haul 
difficult  in  wet  weather  and  sand  will 
make  other  parts  difficult 
in  dry  weather. 

Hauling  on  road  track 
is  an  absolute  certainty 
and  it  makes  no  difference 
whether  the  track  is  rest- 
ing on  sand  or  mud.  By 
using  this  method  a con- 
tractor should  actually  be 
able  to  lay  concrete  twice 
asmanydaysin  theseason 
as  he  would  by  other 
methods. 


Mixing  the  Concrete 

The  operations  involved  in  handling 
the  complete  batches  as  they  arrive  at 


FIG.  6 — Skip  Raised,  Car  lowered  Onto  Running  Gear 

the  mixer  in  road  cars  are  simplified  by 
the  use  of  the  Lakewood 
batch  transfer.  This  is  a 
derrick  arrangement 
attached  to  either  side  of 
the  mixer,  which  lifts  and 
dumps  complete  batches 
directly  into  the  charging 
skip.  Theoperations  are: 

1.  Cement  cover  re- 
moved. Two  men 
attach  Lakewood 
bail  to  car  body. 

2.  Mixer  operator 
owers  skip. 


FIG.  5 — Car  Body  Swung  Back  Over  Running  Gear 

Weight  of  skip  raises  car  from  run 
ning  gear. 

3.  Derrick  is  swung  around  until 
batch  is  over  charging  skip  ready 
to  be  dumped. 

4.  Aggregates  are  dumped  into  charg- 
ing skip. 

5.  Empty  car  body  is  swung  back 
over  running  gear. 

6.  Operator  raises  skip  to  discharge 
batch  into  mixer.  As  skip  rises  car 
body  is  lowered  onto  running  gear. 
Bail  is  detached.  Cycle  of  oper- 
ation is  repeated. 

By  using  this  method  complete  and  cor- 
rectly proportioned  batches  are  dumped 


FIG.  4 — Complete  Batch  Dumped  into  Skip 


(Continued  on  page  16) 


The  Lakewood  Engineering  Co. 


Bulletin  No.  2Q-D 
Page  14 


The 

OLD 

Way 


Compare  These 

Big  wheelbarrow  and  shovel  crews. 

Sand  and  stone  piled  on  grade. 

Aggregates  become  mixed  with  dirt  ot  sub-grade. 

5 to  10  per  cent,  loss  of  material. 

Concrete  work  delayed  until  great  quantity  of  material  can  be 
stocked  on  sub-grade.  Working  season  shortened. 

Sand  and  stone  hauled  over  finished  sub-grade  in  trucks  or 
wagons. 

Certain  amount  of  refinishing  necessary. 

Cement  sacks  must  be  cared  for,  increasing  the  contractor’s 
cost. 

Cannot  operate  in  wet  weather. 

Operation  difficult  on  narrow  roads  and  only  a small  amount  ot 
road  can  be  finished  in  a season. 


Which  Method 


(i 


The  Lakewood  Engitieering  Co. 


Bulletin  No.  2<j-D 
Page  15 


Two  Road  Jobs 


No  wheelbarrow  or  shovel  crews. 

No  stock  piles  on  sub-grade. 

Batches  dumped  from  cars  into  charging  skip. 

Clean  aggregate  assured. 

No  waste  ol  material. 

Concrete  placing  begun  as  soon  as  grading  is  started.  Working 
season  practically  doubled. 

No  hauling  over  sub-grade.  Once  finished,  thesub-grade  needs 
no  further  attention. 

No  cement  sacks  on  the  job.  Cement  bags  emptied  into  cars  at 
central  loading  plant.  Bulk  cement  can  also  be  used. 

Operation  independent  of  weather  conditions. 

System  efficient  on  narrow  and  wide  roads.  Can  finish  more 
than  twice  as  much  road  in  a season. 


The 

LAKEWOOD 

Way 


Will  You  Use? 


'Hie  Lakewood  Engineering  Co. 


Bulletin  No.  29-D 
Page  16 


i;£v*.  1> i£  -■  , 

.1  . - -s 


• V N . -y  . 


Concrete  of  this  consistency  would  be 
difficult  to  work  by  hand  but  the  ma- 
chine handles  it  easily,  as  shown  below. 


directly  into  the  charging  skip,  shovel  and 
wheelbarrow  gangs  are  eliminated,  and  no 
sand,  stone  or  cement  is  piled  on  the  sub- 
grade. No  time  is  lost  shoveling  material 
piles  out  of  the  way  or  bringing  extra  piles 
to  the  mixer.  No  material  is  wasted  from 
misfiguring  the  amount  required  and 
shoveling  the  excess  to  one  side  when  the 
mixer  passes.  The  sand  and  stone  are  kept 
clean — not  mixed  with  the  dirt  of  the 
sub-grade. 

As  the  sand  and  stone  compartments  in 
theroad  cars  hold  just  the  right  amount  to 
make  a correctly  proportioned  batch,  a 
uniform  concrete  mixture  is  obtained 
without  the  cost  and  trouble  of  measur- 
ing each  batch. 

Another  big  advantage  of  this  method 
of  charging  the  mixer  is  that  the  work  of 
the  men  is  made  easier.  There  is  no  wheel- 
ing of  sand  and  stone — no  cement  sacks 
to  empty.  Also,  each  man  has  certain 
duties  which  he  repeats  day  after 
day.  He  learns  to  do  his  particular 
part  of  the  work  better  than  any 
other  man  can  do  it — and  be- 
comes a highly  efficient  workman. 

The  fact  that  the  work  is  easier 
appeals  to  the  men  physically. They 
are  reluctant  to  leave  a compara- 
tively easy  job.  The  labor  turnover 
is  thus  reduced  and  the  cost  of 
securing  new  men  is  saved. 

And  as  the  work  is  systematized 
so  that  each  man  performs  just  one 
operation  and  can  rest  for  a minute 


or  so  at  regular  intervals,  the  few 
men  required  will  work  with  high 
efficiency  throughout  the  day. 

Tamping  and  Finishing  the 
Concrete  Surface 

To  overcome  the  difficulty  of 
finishing  concrete  by  hand  and  to 
permit  the  use  of  drier,  coarser 
mixtures,  a mechanical  concrete 
road  tamping  - finishing  machine 
has  been  perfected. 

This  device  removes  the  air  and  water 
voids  from  the  concrete  and  permits  us- 
ing a very  stiff,  dry  mixture.  The  pro- 
portion of  coarse  aggregate  may  be  in- 
creased considerably  when  this  machine 
is  used. 

This  concrete  road  finisher  has  three 
distinct  functions: 

1 . To  spread  the  concrete  as  it  comes 
from  the  mixer  to  approximately 
the  desired  height  and  crown. 

2.  To  tamp  the  concrete,  remove  the 
voids,  to  compact  the  mixture  and 
work  the  concrete  to  the  finished 
height  and  crown. 

3.  To  float  the  surface  of  the  concrete 

with  a belt  to  a smooth  surface. 

It  performs  this  work  with  a saving  of 
labor  and  at  a faster  speed  than  is  possible 
by  hand  methods. 


A — 


At  Vi  r 5s? 


rr¥ 

b8a#*v!' 


a at 

: -- - 


The  Lakewood  Engineermg  Co. 


Bulletin  No.  29-D 
Page  17 


The  machine  travels  forward  and 
backward  under  its  own  power.  A 
member  called  the  strike-off  spreads 
the  concrete  to  approximately  the 
necessary  height  and  crown. 

The  tamper,  located  just  back 
oi  the  strike-off',  tamps  the  con- 
crete, the  first  time  over  with  a 
long,  hard  stroke;  the  second  time 
with  a short,  rapid  stroke,  which 
may  be  varied  until  the  concrete 
is  being  subjected  to  continuous 
agitation  as  the  machine  moves 
back  and  forth.  The  stroke  of  the 
tamper  is  regulated  by  the  operator  and 
may  be  varied  for  different  consistencies 
of  concrete  as  well  as  for  different  stages 
of  progress. 

The  float,  located  at  the  rear  of  the 
machine,  produces  a smooth  finish  by 
sweeping  a belt  across  the  surface  at  a 
comparatively  slow  speed.  Some  engi- 
neers prefer  to  omit  the  floating  and  have 
used  the  finisher  without  the  belt  attach- 
ment. They  claim  that  the  finish  made 
by  the  rapid  strokes  of  the  tamper  mem- 
ber is  better  than  the  surface  produced 
by  floating.  The  tamper  finish  gives  a 
slightly  roughened  surface  and  an  abso- 
lutely true  crown. 

By  subjecting  the  mixture  to  the  con- 
tinuous agitation  caused  by  the  tamper 
the  concrete  is  compacted  and  the  air  in 
it  is  brought  to  the  surface  as  shown  on 


page  18.  The  larger  stones  and  enough 
mortar  to  cement  them  are  brought  togeth- 
er. By  increasing  the  amount  of  coarse 
aggregate  the  contraction  of  the  concrete 
is  greatly  reduced.  The  voids  are  thus 
eliminated,  and  a concrete  of  mechanically 
uniform  consistency  is  produced. 

This  treatment,  of  course,  results  in  a 
stronger  concrete,  as  has  been  proved  by 
Prof.  Duff  A.  Abrams  in  his  experiments 
at  Lewis  Institute,  Chicago.  Prof. 
Abrams  has  proved  that  30  per  cent,  too 
much  water  reduces  the  strength  about 
one-half  and  twice  the  correct  amount  of 
water  gives  a concrete  of  only  one-fifth 
the  strength  it  would  have  if  just  the  right 
amount  of  water  were  used. 

With  hand  finishing  it  is  necessary  to 
use  water  in  large  excess.  If  this  extra 
amount  of  water  is  not  used  the  concrete 
will  be  so  stiff'  as  to  present  difficulties  in 
finishing.  The  excess  water  reduces 
the  strength  realized  from  the 
cement  and  brings  the  inferior 
materials  and  scum  to  the  top,  pro- 
ducing a poor  wearing  surface. 

The  Lakewood  Concrete  Road 
Finisher  permits  the  use  of  a drier, 
coarser  mixture  than  could  be 
worked  by  hand.  So  dry  a concrete 
can  be  worked  with  this  that  mix- 
ing can  be  done  at  a central  mix- 
ing plant  and  the  concrete  hauled 
long  distances  without  separation 


The  Lakewood  Engineering  Co. 


Bulletin  No.  2Q-D 
Page  /S 


of  the  aggregates.  The  agitation  caused 
by  the  tamper  is  so  violent  that  it  amounts 
to  remixing  the  concrete  and  causes  more 
perfect  hydrating  of  cement. 

Only  one  man  is  needed  to  operate  the 
Lakewood  Road  Finisher.  Because  of  the 
arrangement  of  the  controls  the  machine 
can  be  operated  from  either  side  of  the 
road.  Hence,  one  man  with  the  Lakewood 
machine  and  two  helpers  with  spades  can, 
when  working  dry  concrete,  do  the  work 
usually  done  by  eight  or  nine  men  -atid 
make  a better  road. 

Mixing  at  Central  Plant 

Conditions  on  road  jobs  are  sometimes 
such  that  savings  can  be  effected  by  mix- 
ing the  concrete  at  a central  plant  and 
dumping  mixed  batches  from  cars  onto 
the  sub-grade.  This  is  particularly  true 
when  concrete  is  laid  in  freezing  weather 

when  the  materials  must  be  heated. 

Probably  the  biggest  obstacle  to  the 
use  of  this  method  has  been  working  a 
concrete  of  consistency  that  would  permit 
hauling  any  considerable  distance  without 
separation  of  the  aggregates. 


The  objection  that  such  concrete  can- 
not be  worked  properly  after  a long  haul 
is  overcome  by  the  use  of  the  Lakewood 
Concrete  Road  Finisher. 

So  violent  is  the  action  of  the  tamping 
member  that  the  concrete  is  practically 
remixed,  resulting  in  more  perfect  hydrat- 
ing of  the  cement  and  compacting  the 
concrete  after  the  initial  shrinkage  has 
taken  place,  reducing  hair  checks  and 
other  defects  due  to  contraction.  So 
dry  a mixture  can  be  used  that  the  sepa- 
ration of  the  aggregates  is  practically 
impossible.  By  using  such  concrete  so 
firm  a surface  is  produced  that  it  can  be 
covered  with  straw  or  hay  immediately. 

The  Lakewood  road  car  body  can  be 
used  to  haul  mixed  concrete  by  removing 
the  cement  box.  When  dumped  by  a der- 
rick this  car  body  can  be  turned  squarely 
upside  down.  The  body  being  V-shaped, 
with  a round  bottom  and  sloping  ends, 
dumps  the  concrete  cleaner  than  any 
other  shape  of  bucket. 

The  plant  layouts  shown  on  pages  io 
and  1 i may  be  easily  adapted  to  central 
plant  mixing. 


least  resistance;  air  again  compressed  nearer  surface;  air  bubble  breaking  through  surface;  air  entirely  removed. 

The  Lakewood  Engineering  Co. 


Bulletin  No.  29-D 
Page  19 


y.  • ; d ; T^P/,y 

|Tj  - ■ ! 


■'  ’ • • kjXfo  ^ ^ :•  » •<  } :‘J  ft*  * % A : \Ujk 

>gujvv 

*i»-  - . **•  V'P’V; 

• AbH'b'j  A'A  Tfr* 


• *v  * > 1 1 r . * ‘ *"•  */' ' l { - v*'  * -4  '•>>*  * ; f ‘-i 

yhnh'pSfiii  ■y-y.y. 


Equipment  Used 
In  Building  Roads  With 
Lakewood  Plant 

The  following  pages  give  detailed 
descriptions  of  the  equipment 
needed  for  the  operation  of  the 
Lakewood  Concrete  Road  Plant. 

The  method  of  using  this  plant 
is  outlined  in  the  preceding  pages. 
A more  comprehensive  appreci- 
ation of  the  advantages  of  using 
the  Lakewood  plant  will  be  gained 
if  the  preceding  pages  are  read 
carefully. 

The  equipment  shown  on  pages 
20  to  35,  inclusive,  is,  we  believe, 
best  suited  to  do  the  work  it  is  in- 
tended to  do.  Each  unit  has  been 
designed  and  built  to  work  with 
the  other  units,  thus  giving  a com- 
plete plant  that  will  operate 
smoothly  and  earn  maximum 
profit  for  the  user. 


.*•  s » < v > « <■  s . ; v.  • 

iih 


L_ ww— , — , — m 

■ A'VU.Am’  • H 

m • f?  1$  i ffite  ^ . ■ 3 ■■  - , „ . • ■ ; ■ 

- h • ■ ■ : h ■ ■ ■ Mn  - ■ i w<  ■ 

• . . . ■ ; - ; . ; 

'S  ■ 'y\  ; 

■ ' } ':■■■'  : ' - ' . , . - . . ■ ■ . ' - ■ * , . . 

| ' • 1 , 

■ v.  * • • - -#  • * . • . ' ‘ / '•  ' k;  r ■ *■  1 1 ’ * /-t  * 'i  • * ? vt.‘  > • \ * 


The  Lakewood  Engineering  Co. 


bulletin  No.  2Q-1) 
Page  20 


The  Lakewood  Road  Car 

This  road  car  is  fitted  with  a watertight  cement  box  which  is  bolted  into  place  to 
divide  the  car  into  separate  compartments  for  sand  and  stone.  In  this  car  properly 
proportioned  sand,  stone  and  cement  are  hauled  from  the  central  loading  plant  to  the 
mixer.  The  watertight  cement  compartment  is  bolted  into  the  V-shaped  body  at  a 
variable  distance  from  either  end  of  the  car  to  give  any  desired  proportions.  The 
cement  box  is,  of  course,  provided  with  a removable  watertight  cover. 

These  road  cars  are  fitted  with  a trunnion  arrangement  on  the  ends  of  the  body  so 
that  the  car  body  can  be  lifted  from  the  running  gear  by  means  of  the  Lakewood 
Batch  Transfer  shown  on  page  21. 

By  removing  the  cement  box  the  Lakewood  Road  Car  can  be  used  as  a V-Dump 
car  for  hauling  mixed  concrete  or  dirt.  By  removing  the  body  the  rocker  supports 
are  used  as  bolsters  on  which  to  carry  forms,  pipe,  track,  etc.  Thus  the  Lakewood 
Road  Car  is  three  cars  in  one. 

These  cars  are  equipped  with  spring  drawbars  and  bumpers  to  permit  easy  start- 
ing and  hauling  in  long  trains.  They  are  also  fitted  with  spring  pedestals  to  prevent 
derailments  and  reduce  the  shock  to  cars  and  track  when  hauling  heavy  loads. 

Cage  roller  bearings  make  possible  moving  heavy  loads  with  least  tractive  effort. 
F.xtra  heavy  12-in.  wheels  give  easy  riding  and  hauling  in  long  trains. 

Twenty-four  inch  track  gauge  is  standard. 


The  Lakewood  Engineering  Co. 


bulletin  No.  29-D 
Page  21 


Lakewood  Batch  Box  Cars  and  Batch  Boxes 

Lakewood  batch  box  cars  or  running  gears  are  equipped  with  spring  draw  bars, 
spring  bumpers,  spring  pedestals  and  Hyatt  roller  bearings.  Heat  treated  steel 
axles,  selected  after  a thorough  investigation  of  the  effects  of  rapid  reversal  of  stress 
caused  by  locomotive  haulage,  insure  long,  uninterrupted  service. 

This  Lakewood  car  represents  a big  advance  in  industrial  car  design. 

Two  sizes  of  batch  box  cars  are  available,  one  for  carrying  two  25  cubic  foot  ca- 
pacity boxes,  and  one  for  two  25,  29  or  37  cubic  foot  capacity  boxes. 

The  tip-over  batch  boxes  are  made  of  steel  plate  and  are  loaded  and  handled  with 
the  Lakewood  batch  transfer  in  the  same  manner  as  the  road  car. 

A separate  container  for  cement  divides  the  box  into  compartments  of  proper  size, 
which  when  filled  with  aggregates  and  cement,  give  a batch  of  proper  size  and  pro- 
portions and  prevents  the  mingling  of  aggregates  and  cement. 

The  small  cut  above  shows  two  25  cubic  foot  capacity  batch  boxes  on  the  light 
running  gear  and  the  larger  cut  shows  batch  boxes  of  29  or  37  cubic  foot  capacity 
on  the  heavy  running  gear. 


The  Lakewood  Engineering  Co. 


Bulletin  No.  29-D 
Page  22 


To 


13 

The  Lakewood  Concrete  Road  Finisher 

The  Lakewood  Concrete  Road  Finisher  has  three  distinct  functions:  1.  To  spread 

the  concrete  as  it  comes  from  the  mixer  to  approximately  the  right  height  and  proper 
crown;  2.  To  tamp  the  concrete  to  eliminate  all  voids,  and  compact  the  stone  or  gravel 
aggregate  to  give  a concrete  of  great  density  and  strength;  3.  To  finish  the  surface  of  the 
concrete  with  a belt  to  a smooth,  even-riding  surface. 

It  performs  this  work  with  a saving  of  labor,  at  a fast  speed.  The  resulting  concrete  is 
more  uniform  as  to  strength  and  wearing  qualities  than  is  possible  when  hand  methods 
are  used. 

The  machine  consists,  briefly,  of  a trussed  bridge  over  the  road,  supporting  the  4 h.p. 
gasoline  engine  power  plant  and  driving  mechanism  in  a dust  proof  housing.  The 
bridge  is  carried  on  end  frames  having  two  wheels  each,  traveling  on  the  side  forms. 

A strike-off  with  a metal  edge,  (adjustable  to  the  crown  of  the  road)  and  having  a 
reciprocating  horizontal  movement  across  the  road  is  dragged  by  arms  pivoted  on  the 
axles  of  the  front  wheels. 

Hung  behind  the  strike-off,  on  laminated  springs,  is  the  tamper.  This  consists  of  a 
heavy  timber  (kiln  dried  and  oil  soaked)  shod  with  a steel  channel.  After  many  experi- 
ments this  has  proved  to  be  the  best  construction  for  the  purpose.  The  tamper  has  a 
snappy  down-and-up  movement  and  hits  the  concrete  for  the  full  width  of  the  road  with 
a blow,  the  force  of  which  is  easily  varied  to  suit  the  consistency  of  the  concrete  and  the 
condition  of  its  surface. 

The  finishing  belt  is  attached  to  a supporting  frame  at  the  rear  of  the  machine,  from 
which  it  is  easily  removed  for  cleaning,  reversing  or  renewing.  The  frame  is  shaped  to 
the  crown  of  the  road  and  moves  the  belt  slowly  back  and  forth  across  the  road. 

The  finisher  travels  forward  and  backward  under  its  own  power,  along  the  side  forms. 
The  speed  forward  is  7 ft.  a minute;  reverse,  28  ft.  a minute. 

All  operations  of  the  machine  are  controlled  from  either  side  of  the  road  by  a simple 
system  of  levers.  The  machine  can,  therefore,  be  easily  operated  by  one  man. 

Side  forms  on  which  the  machine  travels  may  be  the  2 in.  boards  often  used,  or  any 
one  of  the  several  types  of  metal  forms  now  on  the  market.  The  only  requirements  for 
the  machine  are  that  the  forms  rest  solidly  on  firm  ground  or  be  supported  by  short 
stakes  driven  into  the  ground  under  them. 


'The  Lakewood  Engineering  Co. 


bulletin  No.  29-D 
Page  23 


Lakewood  Road  Track  and  Joint  Tie 


Narrow  gauge  track  for  road  work  is  ot  the 
most  temporary  kind  and  must  be  laid  down  and 
taken  up  repeatedly.  This  necessitates  a track 
strong  enough  to  stand  this  repeated  rough  han- 
dling. The  track  must  also  have  enough  bearing 
surface  to  support  it  on  natural  ground  without 
ballast. 

Lakewood  Road  Track  meets  these  require- 
ments. The  rails  are  supported  by  a large, 
pressed  steel  tie  with  end  flanges,  developed  for 
use  on  the  European  battlefields  where  track  was 
laid  and  successfully  used  on  extremelysoft  ground. 

These  ties  are  riveted  to  the  rails  to  insure  a 
rigid  track  section,  which 
cannot  shift  by  one  rail 
taking  a lead  over  the 
other,  or  ties  slipping  out 
of  position. 

The  groove  in  the  old 
style  rolled  tie  collects  rain 
water  and  causes  puddles 
under  the  ends  of  ties  on 
the  low  side  of  the  track. 

This  softens  the  support- 
ing ground  at  the  most 
vital  spot.  This  defect  has 
been  overcome  by  the 
Lakewood  pressed  steel  tie 
with  a flange  on  the  end 
as  well  as  on  the  side. 

The  Lakewood  tie  gives 
unusually  large  bearing 


surface  outside  of  the  rail  as  well  as  inside,  thus 
eliminating  buckling  and  permitting  track  to  be 
used  on  extremely  soft  ground. 

Frequent  moving  of  road  track  makes  it  prac- 
tically impossible  to  keep  bolts  in  good  shape  and 
fish  plates  bolted  on  tightly.  The  common  cus- 
tom has  been  to  use  a slip  sleeve,  or  simply  bolt 
fish  plates  to  one  section.  This  does  not  make  a 
reliable  splice,  nor  does  it  support  the  track  im- 
mediately at  the  joint. 

To  overcome  these  objections  Lakewood  has 
developed  the  joint  tie  shown  for  joining  road 
track  together.  It  clamps  the  rails  and  supports 
the  j oint.  The  tie  and 
clamps  are  riveted  to- 
gether and  make  one  solid 
piece  too  big  to  lose 
easily  and  too  rugged  to  be 
damaged  by  handling. 
T his  tie  takes  the  place 
of  four  fish  plates,  eight 
bolts  and  eight  nuts — 
twenty  pieces  in  all — with 
no  threads  to  get  out 
of  order  and  no  bolts  to 
come  loose. 

Various  track  and 
switch  sections  and  spec- 
ifications are  shown  in 
detail  on  the  following 
page. 


The  Lakewood  Engineering  Co, 


The  Lakewood  Engineering  Co 


LAKEWOOD  ROAD  TRACK  DETAILS 


Bulletin  No.  29-D 
Page  25 


The  Lakewood-Milwaukee  Paver 

The  Lakewood-Milwaukee  Paver  has  kept  pace  with  the  growth  in  popu- 
larity of  concrete  as  a material  for  permanent  pavements.  It  has  been  im- 
proved from  year  to  year  to  make  possible  placing  more  concrete  of  better 
quality  in  a given  time. 

The  machine  is  remarkable  in  its  design  for  such  details  as: 

1.  A differential  gearing  on  the  rear  axle  to  permit  turning  in  narrow 
streets  or  roads,  as  with  an  automobile. 

2.  A power  steering  device  that  permits  the  operator  to  guide  the  machine 
with  much  less  effort  and  much  more  truly  than  with  the  old-fashioned 
hand  wheel. 

3.  A highly  developed  steam  engine  to  drive  the  machine,  which  has 
many  unusual  features,  as  described  on  page  30. 

4.  An  unusually  convenient  arrangement  of  all  levers,  so  the  engineer 
can  control  every  operation  of  the  machine  without  moving  around 
the  platform. 

5.  Extra  wide  (14  in.)  wheels  to  give  large  bearing  surface. 

Lakewood-Milwaukee  Pavers  are  driven  by  either  steam  or  gasoline  power 
and  are  equipped  with  distributing  boom  and  bucket  or  with  gravity  chute. 
The  length  of  the  boom  is  16  ft.  and  the  bucket  holds  a complete  batch  of  14 
cu.  ft.  of  mixed  concrete. 

The  distributing  bucket  bottom  doors  are  operated  by  a tripping  and  closing 
device  developed  especially  for  these  mixers.  It  is  not  dependent  on  the 
tension  of  the  cables,  which  may  be  comparatively  slack.  Any  stretch  in  the 
cables  is  automatically  taken  up  on  the  winding  drums.  The  bucket  may  be 
run  out  to  any  point  on  the  boom  and  stopped  without  danger  of  opening 
the  bucket  sooner  than  desired.  The  mechanism  does  not  open  the  doors 
until  the  bucket  starts  on  its  trip  back  to  the  mixer.  The  doors  then  stay 
open  until  just  before  the  mixer  is  reached,  giving  plenty  of  time  for  the  batch 
to  flow  completely  out  of  the  bucket.  There  is,  therefore,  little  danger  of 
jamming  the  doors  with  stones.  Doors  are  heavily  braced  to  withstand  hard 
service,  and  hinges  are  arranged  so  concrete  does  not  overflow  them. 

Gravity  chutes  are  sometimes  preferred  on  narrow  street  or  road  work. 
The  gates  are  easily  operated  and  if  concrete  is  mixed  with  the  proper  amount 
of  water  it  will  easily  flow  down  these  chutes.  The  mixer  end  of  chutes  is 
widened  to  prevent  splashing  of  concrete  as  it  flows  off  the  mixer  discharge 
spout. 

Size  No.  14,  with  boom  and  bucket,  is  recommended  for  use  with  the 
Lakewood  Road  Plant.  This  has  a capacity  of  14  cu.  ft.  of  mixed  concrete 
per  batch.  This  is  the  most  popular  size  with  city  paving  contractors  put- 
ting in  concrete  base  for  various  pavements.  On  this  work  the  machine 
generally  mixes  a 2-bag  batch  of  1-3-5  or  of  1-3-6  concrete. 


The  Lakewood  Engineering  Co. 


Bulletin  No.  2<j- 1) 
Page  26 


Hoisting  Lever 
rolley  Lever 

Brake  Lever 


Drum  Lever 


Main  Clutch  Lever 
Traction  Lever 


Discharging  Lever 
Steering  Lever 


Control  Levers 

All  levers  on  Lakewood-Milwaukee  Pavers  are  easily 
accessible  from  the  operator’s  platform. 


/ he  l , akewood  Engineering  Co. 


Bulletin  No.  29-D 
Page  2/ 


Steering  Clutches 
Lever  Controlled 


Traction  Drive  Shaft  — 
Traction  Reversing  Gear- 
Traction  Jack  Shaft 


Reach  Rod- 


Support  for 

Operator’s 

Platform 


Traction  Drive  Counter  Shaft 


Differential  Gears  in 
Cast  Steel,  Oil  Tight 
Dust  Proof  Housing 


Underslung  Frame  Construction 

Shafts,  traction  and  power  steering  gears  on  Lakewood- 
Milwaukee  Pavers  are  easily  accessible.  Shafts  can  be 
dropped  down  and  removed  without  removing  the  drum 
or  otherwise  dismantling  the  machine. 


The  Lakewood  Engineering  Co. 


Bulletin  No.  2Q-D 
Page  28 


The  Lakewood-Milwaukee  No.  14-E  Paving  Mixer 

(Mixed  Batch  Hating) 


The  Lakewood  Engineering  Co. 


Bulletin  No.  29-D 
Page  29 


Specifications  for  No.  14-E  Lakewood-Milwaukee  Paver 


CAPACITY 

22  cu.  ft.  of  loose  unmixed  material. 

14  cu.  ft.  of  mixed  concrete. 

MIXING  DRUM 

Diameter,  5854" — Length,  47"  Inside 
Dimensions. 

End  Openings,  18&"  diameter. 

Tracker  Surface,  354"  wide. 

Speed  of  Drum,  16  R.  P.  M. 

Drive  Chain. 

TRACKER  WHEELS 


MAIN  FRAME  AND  TRUCKS 

Sills — 8"  tt>  Channels — Length,  93" 

— Width  through  engine  and  boiler 
platform,  106". 

Engine  Platform — 54”  Steel  Plate. 

All-Steel  Truck — 3-point  suspension. 

Wheel  Base,  85"- — Tread,  70". 

Front  Axle,  2-6"  13  lb  Channels,  with 
b lilt-in  high  carbon  steel  axles,  2f|" 
diameter. 

Rear  Axle  Shaft — High  carbon  steel,  3}f " 
diameter 

Front  Wheels— 28"  x 14"  tread. 


Drum  Countershaft — Cold  rolled 
2 i7s  " diameter. 

Engine  Countershaft— Cold  rolled 
2 is"  diameter. 


steel, 

steel. 


CLOSED  WATER  TANK 

Capacity,  30  gallons. 

Length,  28" — Diameter,  18". 
Intake,  154"— Outlet,  254". 


ELECTRIC  MOTOR 

Any  standard  make  — 15  H.  P.  — 900 
R.  P.  M.  preferred. 

Cut  steel  reduction  gears. 


BOOM  AND  BUCKET 

18  ft.  Boom — 14  cu.  ft.  Bucket. 
20  ft.  Boom— 10  cu.  ft.  Bucket. 


Diameter,  16". 

Face,  354”. 

Length  of  Bearing,  12". 

Tracker  Shafts — Cold  rolled  steel,  2, 
diameter. 


Rear  Wheels— 34"  x 14"  tread. 

Driving  Sprockets  bolted  to  rear  wheels. 
Cleats  on  wheel  treads. 

CLUTCHES  AND  COUNTER- 
SHAFTS 

Milwaukee  Internal  Expanding  Toggle 
Clutch. 

Lined  with  non-burning  automobile 
brake  lining. 


STEAM  ENGINE 


(.See  pare  10 ) 


Rated  Horse  Power,  12 — Bore,  8 — 
Stroke,  8" — Speed,  175  R.  P.  M;> 
Steam  Opening,  1}4" — Exhaust,  2 . 
Flywheel,  30"  diameter  x 4"  face. 

Crank  Pin,  2 54"  diameter. 


STEAM  BOILER 

Diameter,  36"— Height  over  all,  84". 
Rated  Horse  Power,  14. 

Shell,  A"  fire  box  steel;  head,  3/s  . 
Tubes— 63,  2"  lap  welded,  56"  long. 
Heating  Surface— 140  square  feet. 
Furnace,  27"  high— 3154"  diameter. 
Grate  Area — 5.1  square  feet. 


Traction  Gearing 

Travel  forward  or  backward  is  controlled  by  only  two  levers  at  the  operator’s  platform. 
One  lever  is  for  the  gear  shift  governing  the  direction  of  travel  and  the  other  lever  controls 
the  friction  clutch.  There  is  a chain  and  sprocket  drive  to  each  rear  wheel.  Power  is  trans- 
mitted to  these  chain  drives  through  a set  of  differential  gears  in  a cast  steel,  oil-tight,  dust- 
proof  housing.  The  differential  permits  turning  the  machine  on  very  narrow  roads  without 
any  slipping  of  the  wheels,  thus  avoiding  strains  on  the  rear  axle  and  driving  mechanism. 


The  Lakewood  Engineering  Co 


Bulletin  No.  29-D 
Page  jo 

* *1.1  ak  i\  ^ 


Lakewood-Milwaukee  Steam 
Engines 

Lakewood-Milwaukee  Steam  Engines  used  in 
the  Pavers  are  of  the  vertical  slide  valve  type. 

The  crosshead  guides,  center  crank  and 
connecting  rod  end,  as  well  as  the  piston  rod 
and  stuffing  box,  are  protected  from  cement 
and  dirt  by  two  side  plates,  held  to  a tight  fit 
to  the  engine  frame  by  hand  latches.  The  life 
of  the  engines  is  accordingly  greatly  increased 
and  repair  bills  are  reduced  to  a minimum. 

All  lubricating  points  are  easily  accessible. 

The  flywheel  is  of  the  solid  disc  type  instead 
of  being  built  as  a wheel  with  spokes.  This  is 
a good  “Safety  First”  feature.  The  flywheel 
is,  moreover,  counterweighted  to  balance  the 
weight  of  the  crank  piston,  connecting  rod, 
etc.,  so  the  engine  runs  smoothly  and  without 
vibration. 


Lakewood  Road  Pumping  Plant 

To  meet  the  needs  of  the  paving  contractor,  the  Lakewood  Engineering 
Company  has  developed  a pumping  outfit  which  will  insure  a full  supply  of 
water  with  the  chances  of  a shut-down  of  the  plant  reduced  to  a minimum. 

This  plant  consists  of  two  separate  pumping  units  mounted  on  one  truck. 
Each  unit  consists  of  an  outside  packed  plunger  pump  driven  by  a Novo 
engine  and  is  capable  of  delivering  1800  gallons  per  hour  with  a pressure  of 
225  pounds  per  square  inch  at  the  pump.  The  pumps  may  be  connected  so 
that  the  supply  is  80  gallons  per  minute  at  a pressure  of  225  pounds  per 
square  inch. 

The  advantages  of  a double  pumping  plant  are  manifest.  A constant 
supply  of  water  is  insured,  for  even  if  one  unit  should  break  down,  the  other 
pump  and  engines  would  supply  water  to  keep  the  job  running. 

Failure  of  water  supply  has  caused  many  paving  jobs  to  be  shut  down  tem- 
porarily with  a resulting  loss  to  the  contractor.  The  Lakewood  pumping 
plant  is  good  insurance  that  the  job  on  which  it  is  working  will  not  have  to 
be  closed  for  lack  of  water. 


The  Lakewood  Engineering  Co. 


Bulletin  No.  29-D 
Page  31 


The  Lakewood  Batch  Transfer 

The  Weight  of  the  Skip  is  the  Lifting  f orce 

By  means  of  the  Batch  Transfer  on  Lakewood  Paving  Mixers,  com- 
plete batches  are  dumped  directly  into  the  charging  skip  as  discussed 
on  pages  12  and  13. 

The  device  permits  the  use  of  a standard  front-charge  Lakewood 
paver  without  incapacitating  it  for  wheelbarrow  or  other  methods  of 
charging. 

No  extra  power  is  required  to  raise  and  lower  the  road  car  bodies. 
The  lifting  is  done  by  the  weight  of  the  descending  skip.  Power  is  thus 
used  that  would  otherwise  be  wasted.  There  is  no  hoist  to  operate. 
Operations  are  timed  properly  and  it  is  impossible  to  drop  the  load  or 
raise  it  at  the  wrong  time. 

The  derrick  is  carried  on  two  wheels,  as  shown,  thus  relieving  the 
mixer  frame  of  any  undue  strains.  This  independent  support  feature 
permits  attaching  the  derrick  to  either  side  of  mixer  in  a few  minutes. 
Any  stress  set  up  by  the  derrick  and  its  load  is  carried  by  a heavy 
channel  directly  to  the  rear  axle. 

By  means  of  a tilting  adjustment,  the  derrick  is  kept  in  working 
position  on  varying  grades,  inclined  so  that  the  load  will  swing  over  the 
charging  skip  by  gravity. 


The  Lakewood  Engineering  Co. 


Bulletin  No.  29-D 
Page  32 


The  Lakewood  Subgrader 


The  Lakewood  Subgrader  was  developed  to  provide  contractors  with  a means  of 
cutting  an  absolutely  accurate  subgrade  at  a minimum  of  expense. 

A series  of  V-shaped  knives  6 inches  wide  and  varying  from  2 to  4 feet  in  length, 
are  mounted  beneath  a wooden  framework.  This  frame  is  supported  by  rollers  run- 
ning on  side-forms.  The  operation  of  a hand  lever  raises  the  machine  on  a pivot 
until  free  of  the  forms.  It  is  then  easily  reversed  or  swung  so  that  the  roller  may  pass. 


The  earth  shaved 
off  by  the  subgrader 
ispiled  in  windrows 
convenient  for 
handling 


The  subgrader  is 
raised  and  swung 
on  a pivot  to  pro- 
vide parsing  room 
for  the  roller 


The  same  crew  sets  the  forms  and  operates  the  subgrader.  The  old  subgrading 
crew  is  almost  entirely  eliminated.  There  is  a reduction  of  50  per  cent  in  the  labor 
and  cost  of  subgrading. 

I'he  machine  is  pulled  by  a road  roller,  which  is  a necessary  part  of  the  sub- 
grade outfit. 

While  pulling  the  subgrader,  the  roller  packs  the  loose  material  spread  by  the 
shovelers  to  fill  inequalities. 

1 he  finished  subgrade  is  true  to  within  Ms-inch  of  the  engineer’s  profile. 

1 here  are  good  money-saving  reasons  for  using  a subgrader.  If  the  subgrade  is 
1 2-inch  low  there  is  a waste  of  146  cubic  yards  of  concrete  in  a mile  of  18~foot  road. 
At  $12  a cubic  yard  this  means  a loss  or  saving  to  the  contractor  of  $1752  a mile. 


The  Lakewood  Engineering  Co. 


Lakewood  Concrete  Mixers  for 
Bridges  and  Culverts 


Bulletin  No.  2g-D 
Page  33 


LAKEWOOD-MILWAUKEE  LOW 
CHARGE  MIXER 


LAKEWOOD  UNIVERSAL  MIXER 


For  culverts,  bridges,  footings  and  other 
jobs  that  are  usually  included  in  highway 
contracts  Lakewood  Low  Charge  or  Lake- 
wood  Universal  Mixers  are  well  fitted. 

Lakewood-Milwaukee  Low  Charge  Mix- 
ers have  a capacity  of  7 cu.  ft.  (mixed 
batch  rating).  Easily  moved  from  job  to 
job.  Fast  and  thorough  mixing  combined 
with  easy  charging  make  these  machines 
popular  for  this  class  of  work. 

Lakewood  Universal  Mixers  are  made 
in  only  one  size  to  hold  7 cu.  ft.  of  mixed 
concrete.  Machine  is  gear  driven.  Gear 
made  of  four  interchangeable  segments. 

Bulletin  21  gives  complete  information 
and  specifications. 


Lakewood  Platform  Car  for  General  Utility  Work 


Platform  cars  of  the  type  shown  are  frequently  used  for  hauling  the  lighter 
equipment,  moving  switches,  turnouts,  etc.,  and  for  transporting  brick  or  bags  of 
cement  for  culvert  work.  Every  list  of 


equipment  should  include  a few  of  these 
general  utility  cars.  Platform  16/x3/  4/r. 
Capacity  5 tons.  Weight  2,000  pounds. 
Equipped  with  spring  drawbars, bump- 
ers and  pedestals. 


3-£ 


- 


‘/If'&rL 


3-7 


24  r^-  -J 


rar* 


TY/=>£ 

<Z&ST  /*PO/V  BOXES  /V/TVr' 
STEEl.  Tl/BC  BuSH/BaS 


The  Lakewood  Engineering  Co. 


Bulletin  No.  29-D 
Page  34 


Lakewood  Clam  Shell  Buckets 

Diggers  and  Handlers 

When  Lakewood  Clam  Shell  Buckets  are  used  with  a derrick  or  crane,  in  conjunction  with 
other  Lakewood  Road  Construction  Plant,  cost  of  unloading  and  handling  material  is  reduced 
to  the  minimum. 

Full  loads  assured  because  the  upper  sheaves  are  on  the  closing  arms.  This  causes  closing 
power  to  increase  and  the  bucket  to  dig  down  as  shells  come  together. 

Lakewood  Buckets  for  handling  are  of  the  same  design  but  made  lighter  in  weight  than 
Lakewood  digging  buckets.  Sizes,  Y2  to  2 cu.  yds. 

Lakewood  Clam  Shells  for  digging  are  made  of  heavier  plate  than  the  handling  bucket 
and  fitted  with  teeth  to  penetrate  hard  material.  Sizes,  EL  to  21  o cu.  yds. 
further  details  of  Lakewood  Clam  Shell  Buckets  are  given  in  Bulletin  26. 


( 


The  Lakewood  Engineering  Co. 


Bulletin  No.  2y-D 
Page  35 


Lakewood  Tunnel  Storage 

With  the  idea  of  insuring  for  road  contractors  practically  continuous  operation  during  the  working 
season,  by  storing  in  the  winter  and  early  spring  a large  part  of  the  season’s  supply  of  aggregates, 
The  Lakewood  Engineering  Company  in  the  spring  of  1919  first  brought  to  the  attention  of  road 
building  contractors  the  tunnel  system  of  stock  piles  for  loading  and  reloading  concrete  materials 
into  narrow-gauge  railroad  cars. 

The  system  was  installed  and  successfully  used  during  the  season  of  1919  by  many  contractors. 

With  the  tunnel  system  train-loads  of  stone  and  sand  are  unloaded  quickly  and  with  the  least 
expenditure  of  money  and  man-power. 

Stock  piles  are  large  enough  to  provide  materials  for  the  continuous  operation  of  the  mixing 
plant,  regardless  of  ordinary  irregularities  in  railroad  service. 

Unloading  railroad  cars  is  independent  of  the  operation  of  the  rest  of  the  road  building  plant. 

Maximum  storage  is  obtained  with  the  smallest  amount  of  yard  space  and  the  shortest  lengths 
of  special  sidings. 

The  tunnel  system  permits  winter  and  early  spring  storage  of  materials — insures  for  the  contrac- 
tor the  completion  of  finished  road  practically  every  day  in  the  season. 

Lakewood  Tunnel  Traps 

An  important  factor  in  the  success  of  the 
tunnel  method  of  material  storage  is  the  tun- 
* nel  trap  designed  especially  for  the  loading 

of  road  cars  or  batch  boxes. 

These  traps  are  properly  spaced  in  the  roof 
of  the  tunnel,  so  that  with  one  spotting  of 
the  train,  all  compartments  can  be  filled  with 
one  kind  of  aggregate.  The  traps  are  also 

Side-View  , f -r.0  , ■ r , . Top  View 

used  successfully  for  charging  cars  from  bins. 

The  inside  dimensions  of  the  top  of  the  tunnel  trap  are  V 8"  by  T 634"  flange  drilled  for  fasten- 
ing to  the  top  of  the  tunnel.  When  the  trap  is  closed  it  projects  1'4H"  below  the  top  of  the  tunnel. 

Economy  of  Using  Bulk  Cement 

The  Lakewood  paving  plant  has  been  designed  to  use  bagged  or  bulk  cement  with  equal  facility. 

However,  because  of  its  economy  on  large  jobs,  bulk  cement  is  recommended  and  should  be 
carefully  considered  by  the  contractor. 

The  actual  saving  by  using  bulk  cement  has  been  proved  to  amount  to  as  much  as  ten  to  fifteen 
cents  per  barrel.  On  a large  job,  justifying  the  installation  of  a complete  plant,  the  cement  used 
will  be  as  much  as  100,000  barrels,  or  even  more,  on  which  the  saving  by  using  bulk  cement 
would  be  approximately  $10,000  to  $15,000. 

The  greatest  economy  will  result  if  the  bulk  cement  is  handled  by  a clam  shell  bucket  direct 
from  gondola  cars  to  the  storage  house  as  outlined  in  plant  lay  out  M-232  on  page  1 1.  Even  if 
the  cement  is  shipped  in  box  cars  it  can  be  unloaded  into  storage  at  only  slightly  more  cost,  but 
the  economy  will  still  be  very  great. 


The  Lakewood  Engineering  Co. 


Bulletin  No.  29-D 
Page  36 


Lakewood  Grouters  for  Brick  Roads 

When  grout  is  mixed  in  this  Lakewood  M-C  Grout  Mixer 
the  saving  in  cement  soon  pays  for  the  machine.  The  time 
of  2 or  3 men  can  usually  be  added  to  the  saving  in  cement. 
Better  grout  results  than  when  hand  methods  are  used. 
Described  fully  in  M-C  Bulletin  32.  Immediate  delivery. 


The  Lakewood  Engineering  Co. 


Bulletin  No.  29-D 
Page  37 


Table  1 

Quantity  of  Materials  Required  for  One  Cubic  Yard  of  Rammed  Concrete, 
Based  on  a Barrel  of  4 Cubic  Feet  of  Cement* 


Proportion  by 
Parts 


Vol. 

Cu. 

Ft. 


PERCENTAGE  OF  VOIDS  IN  BROKEN  STONE  OR  PEBBLES 


Cement 

Sand 

Stone 

Loose 

50% 

45% 

40% 

30% 

Bags 

Cu. 

Ft. 

Cu. 

Ft. 

Cu. 

Ft. 

Cement 

Sand 

Stone 

Cement 

Sand 

Stone 

[Cement 

Sand 

Stone 

Cement 

Sand 

<U 

C 

O 

c n 

1 

134 

3 

sy2 

2.01 

0.45  | 0.89 

1.91 

0.42 

0.85 

1.83 

0.41 

0.81 

1.68 

0.37 

0.75 

1 

2 

3 

6 

1.81 

0.54 

0.80 

1.74 

0.52 

0.77 

1.67 

0.50 

0.74 

1.54 

0.46 

0.68 

1 

2 

6 y2 

1.71 

0.51 

0.89 

1.64 

0.49 

0.85 

1.57 

0.46 

0.81 

1.44 

0.43 

0.75 

1 

2 

4 

7 

1.58 

0.47 

0.94 

1.51 

0.45 

0.89 

1.44 

0.43 

0.85 

1.32 

0.39 

0.78 

1 

2M 

4 

iVi 

1.46 

0.54 

0.87 

1.39 

0.51 

0.82 

1.33 

0.49 

0.79 

1.23 

0.46 

0.73 

1 

3 

5 

9 

1.22 

0.54 

0.90 

1.16 

0.52 

0.86 

1.11 

0.49 

0.82 

1.02 

0.45 

0.76 

*From  Taylor  & Thompson  “Concrete,  Plain  and  Reinforced.” 


Table  2 

Area  of  Cross-Section,  Cubic  Yards  Concrete  per  Lineal  Foot  and  Mile, 
and  Square  Yards  Pavement  per  Mile 


Width 
in  Ft. 

THICKNESS 

Area 

Cross  Section 
Sq.  Ft. 

Cubic  Yds. 
Concrete 
per  Lineal 
Foot  of 
Pavement 

Cubic  Yds. 
Concre  te 
per  Mile 

Square 
Yards  per 
Mile 

Side 

Inches 

Center 

Inches 

Average 

Inches 

10 

5 

6 

5.666 

4.722 

.175 

924 

5,866 

10 

5 

7 

6.333 

5.277 

.195 

1,030 

5,866 

10 

6 

8 

7.333 

6.111 

.226 

1,193 

5,866 

10 

7 

8 

7.666 

6.387 

.237 

1,251 

5,866 

12 

5 

6 

5.666 

5.666 

.210 

1,109 

7,040 

12 

5 

7 

6.333 

6.333 

.235 

1,241 

7,040 

12 

6 

7 

6.666 

6.666 

.247 

1,304 

7,040 

12 

6 

8 

7.333 

7.333 

.272 

1,436 

7,040 

14 

5 

6 

5.666 

6.610 

.245 

1,294 

8,213 

14 

5 

7 

6.333 

7.388 

.273 

1,441 

8,213 

14 

6 

7 

6.666 

7.777 

.288 

1,521 

8,213 

14 

6 

8 

7.333 

8.555 

.317 

1,674 

8,213 

16 

5 

7 

6.333 

8.443 

.313 

1,653 

9,387 

16 

6 

7 

6.666 

8.888 

.329 

1,737 

9,387 

16 

6 

8 

7.333 

9.777 

.362 

1,911 

9,387 

16 

7 

8 

7.666 

10.219 

.378 

1,996 

9,387 

18 

6 

8 

7.333 

1 1 .000 

.407 

2,149 

10,560 

18 

7 

8 

7.666 

11.497 

.426 

2,249 

10,560 

18 

7 

9 

8.333 

12.500 

.463 

2,445 

10,560 

18 

8 

10 

9.333 

14.000 

.519 

2,740 

10,560 

20 

6 

8 

7.333 

1 9 999 

.453 

2,392 

1 1 ,733 

20 

7 

9 

8.333 

13.888 

.514 

2,714 

1 1,733 

20 

8 

10 

9.333 

15.555 

.576 

3,041 

1 1,733 

22 

6 

8 

7.333 

13.444 

.498 

2,629 

1 2,907 

22 

7 

9 

8.333 

15.277 

.566 

2,988 

1 2,907 

22 

8 

10 

9.333 

17.109 

.634 

3,348 

12,907 

The  Lakewood  Engineering  Co. 


Bulletin  No.  29-D 
Page  j8 


LAKEWOOI ) INDUSTRIAL 
HAULAGE 

Flat  Wheel  and  Flange  Wheel 

Storage  Battery  Tractors 
Storage  Battery  Trucks 
Four-Wheel  Steer  Trailers 
Factory  Trailers 
V-Dump  Trailers 
Hand  Trucks 


Storage  Battery  Locomotives 

Trolley  Locomotives 

Industrial  Cars 

V-Dump  Cars 

Charging  Cars 

Core  Oven  Cars 

Foundry  Cars 

Track  and  Switches 


In  selecting  the  types  of  haulage 
equipment  best  adapted  to  conditions 
in  your  plant,  Lakewood  Engineers 
can  help  you.  A request  for  their 
service  involves  no  obligation.  Bulle- 
tins on  request. 


4 


< 


( 


The  Lak  ewood  Engineering  Co. 


Bullet  in  No.  29- D 
Page  39 


* 


LA KEWOOD  CONSTRUC- 
TION PLANT 

Lakewood-Milwaukee 
Low-Charge  Mixers 
Lakewood-Milwaukee 
Building  Mixers 
Lakewood  M C Rail  Track 
Mixers 

Lakewood  Mixers 
Lakewood-Milwaukee  Pavers 
Lakewood  M-C  Grouters 
Mortar  Mixers 
Concrete  Chutes 
Concrete  Carts 
Steel  Towers 
Steel  Booms 
Elevating  Buckets 
Dumping  Buckets 
Floor  Hoppers 
Skips — Sleds 
Clam  Shell  Buckets 
V-Dump  Cars 
Concrete  Cars 
Radial  Gate  Cars 
Narrow-Gauge  Portable  Track, 
Switches  and  Turntables 
Concrete  Road  Finisher 

Lakewood  Engineers  can  help 
select  and  arrange  plant  to  earn 
a maximum  profit  for  the  user. 


The  Lakewood  Engineering  Co. 


